Search this show’s transcripts

The History of Chemistry

en us
Chemistry is everywhere, and involves everything. But how did chemistry get to be what it is? I'm Steve Cohen, a chemist and writer, bringing you The History of Chemistry. This podcast explores the development of chemistry from prehistoric times to the present, including the people and societies who made chemistry what it is today. The History of Chemistry is for you, whether you hated chemistry in high school, or got a PhD in inorganic chemistry. We'll explore how chemistry affected art, music, language, politics and vice-versa. Whether it's ancient Greek philosophers, medieval alchemists, or modern laboratory apparatus, it's all here. Don't forget to support my series at https://www.patreon.com/thehistoryofchemistry !
More details
Chemistry is everywhere, and involves everything. But how did chemistry get to be what it is? I'm Steve Cohen, a chemist and writer, bringing you The History of Chemistry. This podcast explores the development of chemistry from prehistoric times to the present, including the people and societies who made chemistry what it is today. The History of Chemistry is for you, whether you hated chemistry in high school, or got a PhD in inorganic chemistry. We'll explore how chemistry affected art, music, language, politics and vice-versa. Whether it's ancient Greek philosophers, medieval alchemists, or modern laboratory apparatus, it's all here. Don't forget to support my series at https://www.patreon.com/thehistoryofchemistry !
Sources and links
Website Apple RSS

Episodes

Page 3 · 50 per page
Published 2023-09-10

85: Great Balls of Fire

21 min
View

A new form, or allotrope, of the element carbon was discovered in the 1980s, and we hear of the story, centering on three chemistry professors: Harry Kroto, Richard Smalley, and Robert Curl. But they couldn't definitively show the molecular structure of their discovery, though they believed strongly, with circumstantial evidence, that it was soccerball-shaped. A few years later, Wolfgang Krätschmer and American Donald Huffman learned how to make significant quantities of this molecule, and showed that the trio were right.

Support the show

More description

A new form, or allotrope, of the element carbon was discovered in the 1980s, and we hear of the story, centering on three chemistry professors: Harry Kroto, Richard Smalley, and Robert Curl. But they couldn't definitively show the molecular structure of their discovery, though they believed strongly, with circumstantial evidence, that it was soccerball-shaped. A few years later, Wolfgang Krätschmer and American Donald Huffman learned how to make significant quantities of this molecule, and showed that the trio were right.

Support the show

Extract Knowledge
Listen elsewhere
Audio Apple
Published 2023-09-03

84: Tunnel Vision

21 min
View

We explore the story of a new way to "see" atoms on surfaces invented in the 1970s and 1980s, scanning probe microscopy. We hear of Gerd Binnig, and Heinrich Rohrer, at the Zürich branch of IBM research, and how they came up with the scanning tunneling microscope in the late 1970s. Then in the mid-1980s, more IBM researchers invented a sibling technique, atomic force microscopy, which is good for non-conducting surfaces. Both techniques caused quite a splash in the scientific world, and made people wonder what it is they were seeing using these tools, and is it really a form of "seeing"?

Support the show

More description

We explore the story of a new way to "see" atoms on surfaces invented in the 1970s and 1980s, scanning probe microscopy. We hear of Gerd Binnig, and Heinrich Rohrer, at the Zürich branch of IBM research, and how they came up with the scanning tunneling microscope in the late 1970s. Then in the mid-1980s, more IBM researchers invented a sibling technique, atomic force microscopy, which is good for non-conducting surfaces. Both techniques caused quite a splash in the scientific world, and made people wonder what it is they were seeing using these tools, and is it really a form of "seeing"?

Support the show

Extract Knowledge
Listen elsewhere
Audio Apple
Published 2023-08-27

83: Measure Twice, Cut Once

25 min
View

We talk about the development of the metric system, the units chemists use in their laboratories and calculations. We start with John Wilkins and Gabriel Mouton, who were ahead of their time in proposing a universal system of units. After the French Revolution, Talleyrand sponsored a logical set of units for France, which became the metric system. We talk about the early units of metric measurement, in both space and time. The we talk of its expansion across Europe and the world in the 19th and 20th centuries, and new official units added to make measurements and observations more consistent. We end with a brief mention of several non-metric or non-official units chemists still use.

Support the show

More description

We talk about the development of the metric system, the units chemists use in their laboratories and calculations. We start with John Wilkins and Gabriel Mouton, who were ahead of their time in proposing a universal system of units. After the French Revolution, Talleyrand sponsored a logical set of units for France, which became the metric system. We talk about the early units of metric measurement, in both space and time. The we talk of its expansion across Europe and the world in the 19th and 20th centuries, and new official units added to make measurements and observations more consistent. We end with a brief mention of several non-metric or non-official units chemists still use.

Support the show

Extract Knowledge
Listen elsewhere
Audio Apple
Published 2023-08-20

82: Diamond in the Rough

19 min
View

In this episode we talk about the second successful method to make laboratory diamonds, chemical vapor deposition, invented by William Eversole of Union Carbide in 1958. The method was slowly improved over the 1960s and 70s in the USA and Soviet Union, but took a huge leap forward with S. Matsumoto’s research in Japan in the early 1980s. Then we discuss uses for CVD diamonds, and details of making gem-quality CVD diamonds. 

Support the show

More description

In this episode we talk about the second successful method to make laboratory diamonds, chemical vapor deposition, invented by William Eversole of Union Carbide in 1958. The method was slowly improved over the 1960s and 70s in the USA and Soviet Union, but took a huge leap forward with S. Matsumoto’s research in Japan in the early 1980s. Then we discuss uses for CVD diamonds, and details of making gem-quality CVD diamonds. 

Support the show

Extract Knowledge
Listen elsewhere
Audio Apple
Published 2023-08-13

81: Cover Story

21 min
View

We talk of historical developments in surface chemistry of the 1960s and 1970s. With new ultra-high-vacuum chambers now available, chemists began to study the surface structure of metals, oxides, and other salts, plus semiconductors. They discovered surface relaxation and reconstruction. They employed techniques such as electron-diffraction and photoelectron spectroscopy, along with Auger-electron experiments and thermal desorption, and total internal reflection of light--all of which are explained in this episode. We end with a brief discussion of two luminaries of the field, Gabor Somorjai and Gerhard Ertl. My Patreon supporters can download a supplemental sheet to help diagram ideas mentioned.

Support the show

More description

We talk of historical developments in surface chemistry of the 1960s and 1970s. With new ultra-high-vacuum chambers now available, chemists began to study the surface structure of metals, oxides, and other salts, plus semiconductors. They discovered surface relaxation and reconstruction. They employed techniques such as electron-diffraction and photoelectron spectroscopy, along with Auger-electron experiments and thermal desorption, and total internal reflection of light--all of which are explained in this episode. We end with a brief discussion of two luminaries of the field, Gabor Somorjai and Gerhard Ertl. My Patreon supporters can download a supplemental sheet to help diagram ideas mentioned.

Support the show

Extract Knowledge
Listen elsewhere
Audio Apple
Published 2023-08-06

80: I Call Your Name

22 min
View

We discuss the origins of names in organic chemistry, starting the with chaos when Lavoisier and friends didn't create such a terminology in the 1780s. August Hofmann, in the 1860s, began to systematize things for his students, but it didn't take hold. Charles Friedel, though, got an International Congress of Chemistry in 1889 to consider the problem, which created an 1892 Geneva Nomenclature Congress. Finally some sense began to creep into organic nomenclature, and this eventually led to IUPAC after World War I. 

Support the show

More description

We discuss the origins of names in organic chemistry, starting the with chaos when Lavoisier and friends didn't create such a terminology in the 1780s. August Hofmann, in the 1860s, began to systematize things for his students, but it didn't take hold. Charles Friedel, though, got an International Congress of Chemistry in 1889 to consider the problem, which created an 1892 Geneva Nomenclature Congress. Finally some sense began to creep into organic nomenclature, and this eventually led to IUPAC after World War I. 

Support the show

Extract Knowledge
Listen elsewhere
Audio Apple
Published 2023-07-30

79: Suit Yourself

21 min
View

Rather than talk about how chemistry changed society, this episode discusses the inverse: how society changed chemistry, and for the better. We talk much about the 1973 sex-discrimination lawsuit which Dr. Shyamala Rajender filed against the University of Minnesota and its chemistry department, and how sexism pervaded many academic chemistry departments throughout the USA, even for decades thereafter.

Support the show

More description

Rather than talk about how chemistry changed society, this episode discusses the inverse: how society changed chemistry, and for the better. We talk much about the 1973 sex-discrimination lawsuit which Dr. Shyamala Rajender filed against the University of Minnesota and its chemistry department, and how sexism pervaded many academic chemistry departments throughout the USA, even for decades thereafter.

Support the show

Extract Knowledge
Listen elsewhere
Audio Apple
Published 2023-07-23

78: Guiding Light

21 min
View

We learn about the development of the LED, the rival display technology to the LCD. We start with Henry Round's 1907 observations, "Losev light" as per Oleg Losev in the 1920s and the patent he obtained, Rubin Braunstein of RCA in the 1950s, Kurt Lehovec's model of LEDs in the 1950s, then Robert Biard and Gary Pittman at Texas Instruments in 1961. The first inarguable LED was built by Nick Holonyak and friends at General Electric in 1962. We hear of improvements in technology through the 1960s and early 1970s, leading to LED watches and calculators--but not full-color displays or tail-lamps for cars.

Support the show

More description

We learn about the development of the LED, the rival display technology to the LCD. We start with Henry Round's 1907 observations, "Losev light" as per Oleg Losev in the 1920s and the patent he obtained, Rubin Braunstein of RCA in the 1950s, Kurt Lehovec's model of LEDs in the 1950s, then Robert Biard and Gary Pittman at Texas Instruments in 1961. The first inarguable LED was built by Nick Holonyak and friends at General Electric in 1962. We hear of improvements in technology through the 1960s and early 1970s, leading to LED watches and calculators--but not full-color displays or tail-lamps for cars.

Support the show

Extract Knowledge
Listen elsewhere
Audio Apple
Published 2023-07-16

77: Moody Blues

23 min
View

This episode covers the 1960s history of RCA's work on liquid crystal displays, their version of a TV screen one can hang on a wall. We begin with Richard Williams in 1962, who discovered that liquid crystals get a "crinkled" look under a microscope when you apply voltage. George Heilmeier then discovered a guest-host effect with liquid crystals, and even more, found dynamic scattering. RCA showed off its display prototypes to big fanfare in 1968. James Fergason, an independent researcher, patented a way to show temperature with liquid crystal colors, then invented the twisted-nematic field-effect liquid-crystal display in 1968. With Fergason's method, by the 1970s, LCD watches and calculators were being mass-produced. Finally, in 1977, Sivaramakrishna Chandrasekhar discovers a new type of liquid crystal: columnal liquid crystals.

Support the show

More description

This episode covers the 1960s history of RCA's work on liquid crystal displays, their version of a TV screen one can hang on a wall. We begin with Richard Williams in 1962, who discovered that liquid crystals get a "crinkled" look under a microscope when you apply voltage. George Heilmeier then discovered a guest-host effect with liquid crystals, and even more, found dynamic scattering. RCA showed off its display prototypes to big fanfare in 1968. James Fergason, an independent researcher, patented a way to show temperature with liquid crystal colors, then invented the twisted-nematic field-effect liquid-crystal display in 1968. With Fergason's method, by the 1970s, LCD watches and calculators were being mass-produced. Finally, in 1977, Sivaramakrishna Chandrasekhar discovers a new type of liquid crystal: columnal liquid crystals.

Support the show

Extract Knowledge
Listen elsewhere
Audio Apple
Published 2023-07-09

76: The Final Frontier

23 min
View

We hear about such chemistry-related inventions NASA was involved in during the 1960s and 1970s: Mylar blankets, lithium hydroxide to absorb carbon dioxide, silicate anticorrosion coatings, memory foam, scratch-resistant coatings for lenses, spectroscopic water-quality monitoring, special rubber for tires, antifogging spray for optics, non-flammable cloth, and special tiles for spacecraft re-entry. We learn a bit of how they were made or invented, and why.

Support the show

More description

We hear about such chemistry-related inventions NASA was involved in during the 1960s and 1970s: Mylar blankets, lithium hydroxide to absorb carbon dioxide, silicate anticorrosion coatings, memory foam, scratch-resistant coatings for lenses, spectroscopic water-quality monitoring, special rubber for tires, antifogging spray for optics, non-flammable cloth, and special tiles for spacecraft re-entry. We learn a bit of how they were made or invented, and why.

Support the show

Extract Knowledge
Listen elsewhere
Audio Apple
Published 2023-07-02

75: Mercy Mercy Me (The Ecology)

24 min
View

The 1970s brought more environmental concerns: Acid rain, as described by Gene Likens, Herbert Bormann, and Noye Johnson in the USA, and Svante Odén in Europe. Their combined effort brought forth international cooperation to protect agriculture, architecture, and culture. Sherwood Roland and Mario Molina discovered that chlorofluorocarbons, the magic chemicals for refrigeration since the 1920s, would destroy the ozone layer in the atmosphere. Then we mention lead paints, and their hazards. Finally we talk about the Love Canal disaster in New York State, which permanently tainted the chemical industry.

Support the show

More description

The 1970s brought more environmental concerns: Acid rain, as described by Gene Likens, Herbert Bormann, and Noye Johnson in the USA, and Svante Odén in Europe. Their combined effort brought forth international cooperation to protect agriculture, architecture, and culture. Sherwood Roland and Mario Molina discovered that chlorofluorocarbons, the magic chemicals for refrigeration since the 1920s, would destroy the ozone layer in the atmosphere. Then we mention lead paints, and their hazards. Finally we talk about the Love Canal disaster in New York State, which permanently tainted the chemical industry.

Support the show

Extract Knowledge
Listen elsewhere
Audio Apple
Published 2023-06-25

74: Laser Squad

21 min
View

This episode shows the give and take between applied physics, that is, the development of the laser, and chemistry, that is, media in which laser action can take place. We start with Albert Einstein's idea, Valentin Fabrikant's doctoral dissertation and (initially failing) patent. But simultaneously Charles Townes came up with a maser, producing microwaves, and his brother-in-law, Arthur Schawlow's idea of extending the maser into the visible wavelengths, overlapping with Gordon Gould's idea of a laser (and the word laser). We then shift to Richard Zare's work with lasers in chemistry experiments, followed by several inventors of the chemical dye laser. We speak of laser-induced spectroscopy and van der Waals complexes of molecules. 

Support the show

More description

This episode shows the give and take between applied physics, that is, the development of the laser, and chemistry, that is, media in which laser action can take place. We start with Albert Einstein's idea, Valentin Fabrikant's doctoral dissertation and (initially failing) patent. But simultaneously Charles Townes came up with a maser, producing microwaves, and his brother-in-law, Arthur Schawlow's idea of extending the maser into the visible wavelengths, overlapping with Gordon Gould's idea of a laser (and the word laser). We then shift to Richard Zare's work with lasers in chemistry experiments, followed by several inventors of the chemical dye laser. We speak of laser-induced spectroscopy and van der Waals complexes of molecules. 

Support the show

Extract Knowledge
Listen elsewhere
Audio Apple
Published 2023-06-18

73: Living in the Plastic Age

22 min
View

In this episode we hear of developments in the 1970s concerning polymers such as polycarbonate, Hytrel®, PET, polyacetals, Vamac®, PEEK, fluoroelastomers, use of metallocenes to fine-tune properties of polyethylene, and conductive polymers, both inorganic and organic.

Support the show

More description

In this episode we hear of developments in the 1970s concerning polymers such as polycarbonate, Hytrel®, PET, polyacetals, Vamac®, PEEK, fluoroelastomers, use of metallocenes to fine-tune properties of polyethylene, and conductive polymers, both inorganic and organic.

Support the show

Extract Knowledge
Listen elsewhere
Audio Apple
Published 2023-06-11

72: What's in a Name?

20 min
View

We see how naming inorganic compounds has evolved from the early 18th century to now. Initially chemists named compounds by their properties or origin. Then Lavoisier and friends created a new naming scheme based on elemental constituents, but this scheme didn't allow for multiple compounds with different amounts of elements. A variety of schemes appeared in the 19th and early 20th centuries, and this episode talks a bit about who and how these systems came about, and what is used now.

Support the show

More description

We see how naming inorganic compounds has evolved from the early 18th century to now. Initially chemists named compounds by their properties or origin. Then Lavoisier and friends created a new naming scheme based on elemental constituents, but this scheme didn't allow for multiple compounds with different amounts of elements. A variety of schemes appeared in the 19th and early 20th centuries, and this episode talks a bit about who and how these systems came about, and what is used now.

Support the show

Extract Knowledge
Listen elsewhere
Audio Apple
Published 2023-06-04

71: Toxic Relationship

21 min
View

We review the other three of Japan's Big Four Pollution Diseases: Minamata disease, discovered in the 1950s and understood by the late 1960s; Yokkaichi asthma, discovered around 1960 and mostly understood by the early 1970s; and Niigata Minamata disease, discovered in 1965 and resolved by 1971. All four were created by corporations polluting the local environment, and then denying their activities. Mercury pollution is discussed in detail. We hear from special guest Dr. Myra Weiner, who discusses the principles of toxicology.

Support the show

More description

We review the other three of Japan's Big Four Pollution Diseases: Minamata disease, discovered in the 1950s and understood by the late 1960s; Yokkaichi asthma, discovered around 1960 and mostly understood by the early 1970s; and Niigata Minamata disease, discovered in 1965 and resolved by 1971. All four were created by corporations polluting the local environment, and then denying their activities. Mercury pollution is discussed in detail. We hear from special guest Dr. Myra Weiner, who discusses the principles of toxicology.

Support the show

Extract Knowledge
Listen elsewhere
Audio Apple
Published 2023-05-28

70: Go with the Flow

22 min
View

We hear about the discovery of liquid crystals by Friedrich Reinitzer in 1888, through Georges Friedel's compendium in 1922 describing main types of liquid crystals. Around that time the first electromagnetic properties of liquid crystals were described by M. Jezewski, and further researched by W. Kast, Vsevolod Frederiks, and A. Repiewa. The first use of these properties was patented by the Levin brothers in 1936. A revival of research into liquid crystals began post-World War II by George Gray and then Glenn Brown by the early 1960s, which is when we reach the invention of two liquid-crystalline polymers, Kevlar and Nomex. My Patreon subscribers can download a supplemental sheet for diagrams of some of these materials.

Support the show

More description

We hear about the discovery of liquid crystals by Friedrich Reinitzer in 1888, through Georges Friedel's compendium in 1922 describing main types of liquid crystals. Around that time the first electromagnetic properties of liquid crystals were described by M. Jezewski, and further researched by W. Kast, Vsevolod Frederiks, and A. Repiewa. The first use of these properties was patented by the Levin brothers in 1936. A revival of research into liquid crystals began post-World War II by George Gray and then Glenn Brown by the early 1960s, which is when we reach the invention of two liquid-crystalline polymers, Kevlar and Nomex. My Patreon subscribers can download a supplemental sheet for diagrams of some of these materials.

Support the show

Extract Knowledge
Listen elsewhere
Audio Apple
Published 2023-05-21

69: Look for the Union Label

21 min
View

We examine the founding of the International Union for Pure and Applied Chemistry, the organization that sets standards for names of elements and compounds, starting with the first international chemical congress at Karlsruhe, Germany, the 1892 Geneva Rules, a 1911 International Association of Chemical Societies, and finally the IUPAC founded in 1919. We look at some of the controversies over committees trying formulate rules for naming compounds, and what and where exactly the IUPAC is.

Support the show

More description

We examine the founding of the International Union for Pure and Applied Chemistry, the organization that sets standards for names of elements and compounds, starting with the first international chemical congress at Karlsruhe, Germany, the 1892 Geneva Rules, a 1911 International Association of Chemical Societies, and finally the IUPAC founded in 1919. We look at some of the controversies over committees trying formulate rules for naming compounds, and what and where exactly the IUPAC is.

Support the show

Extract Knowledge
Listen elsewhere
Audio Apple
Published 2023-05-15

68: Transuranium Elements

23 min
View

We discuss the discovery of elements 93 to 103, from 1940 through the early 1960s. We hear of Enrico Fermi's work, Otto Hahn and Lise Meitner's discovery of fission, McMillan and Abelson's success, and then the long tenure of Glenn Seaborg discovering elements. Albert Ghiorso was added to the mix. There were Cold War controversies over discoveries at Berkeley versus Dubna and even the Nobel Institute in Sweden. IUPAC was inconsistent with its imprimatur on discovery. Finally, we hear something of the tribulations and difficulties in doing radioactive analytical chemistry on tiny amounts of elements.

Support the show

More description

We discuss the discovery of elements 93 to 103, from 1940 through the early 1960s. We hear of Enrico Fermi's work, Otto Hahn and Lise Meitner's discovery of fission, McMillan and Abelson's success, and then the long tenure of Glenn Seaborg discovering elements. Albert Ghiorso was added to the mix. There were Cold War controversies over discoveries at Berkeley versus Dubna and even the Nobel Institute in Sweden. IUPAC was inconsistent with its imprimatur on discovery. Finally, we hear something of the tribulations and difficulties in doing radioactive analytical chemistry on tiny amounts of elements.

Support the show

Extract Knowledge
Listen elsewhere
Audio Apple
Published 2023-05-09

67: Let's Scratch the Surface

23 min
View

In this episode we encounter for the first time early chemistry of surfaces, including the problem of how to separate the effects of a surface versus the rest of a chunk of material. Pliny the Elder first talked of surface effects, and Benjamin Franklin did some experiments in London. We hear of 19th-century Anne Pockels and her apparatus to measure surface effects of soap in water. Then we learn of Irving Langmuir's extensive work on molecules on liquid surfaces in the 1920s, and how Katharine Blodgett extended his research. The 1930s saw the development of the electron microscope which could resolve images better than light, and Erwin Müller in 1955 first imaged individual atoms on crystal surfaces with a field-ion microscope. By the 1960s engineering improved to attain ultra-high vacuums to keep surfaces from air contamination.

Support the show

More description

In this episode we encounter for the first time early chemistry of surfaces, including the problem of how to separate the effects of a surface versus the rest of a chunk of material. Pliny the Elder first talked of surface effects, and Benjamin Franklin did some experiments in London. We hear of 19th-century Anne Pockels and her apparatus to measure surface effects of soap in water. Then we learn of Irving Langmuir's extensive work on molecules on liquid surfaces in the 1920s, and how Katharine Blodgett extended his research. The 1930s saw the development of the electron microscope which could resolve images better than light, and Erwin Müller in 1955 first imaged individual atoms on crystal surfaces with a field-ion microscope. By the 1960s engineering improved to attain ultra-high vacuums to keep surfaces from air contamination.

Support the show

Extract Knowledge
Listen elsewhere
Audio Apple
Published 2023-05-03

66: Plastic Dreams

22 min
View

The 1960s continued to bring forth new polymers: Stephanie Kwolek, and Kevlar; Wilfred Sweeney and Nomex; USDA and superabsorbent polymers; ionomers; polysulfones; Carl Marvel and polybenzimidazole fibers; and a now-global innovation using polyethylene. We hear about all these polymers, their molecular structures, and the people who developed them. Become a Patreon supporter, and download a supplemental sheet showing their molecular structures.

Support the show

More description

The 1960s continued to bring forth new polymers: Stephanie Kwolek, and Kevlar; Wilfred Sweeney and Nomex; USDA and superabsorbent polymers; ionomers; polysulfones; Carl Marvel and polybenzimidazole fibers; and a now-global innovation using polyethylene. We hear about all these polymers, their molecular structures, and the people who developed them. Become a Patreon supporter, and download a supplemental sheet showing their molecular structures.

Support the show

Extract Knowledge
Listen elsewhere
Audio Apple
Published 2023-04-26

65: Down to Earth

21 min
View

We finally reach the point in our chemical history that environmental chemistry appears, with Rachel Carson, and her book, Silent Spring. We hear about her research and earlier writings, leading up to the publication of the book, and how many chemical organizations and government officials tried to spread “fake news” about her. The second event at this time was Claire Patterson’s work on environmental effects of lead, and his battle against Dr. Robert Kehoe of the Ethyl Corporation. By the late 1960s, Lake Erie was declared dead and the Cuyahoga River briefly caught fire, and the American public had had enough. Earth Day happened in 1970, the EPA was founded in 1971, and here we are.

Support the show

More description

We finally reach the point in our chemical history that environmental chemistry appears, with Rachel Carson, and her book, Silent Spring. We hear about her research and earlier writings, leading up to the publication of the book, and how many chemical organizations and government officials tried to spread “fake news” about her. The second event at this time was Claire Patterson’s work on environmental effects of lead, and his battle against Dr. Robert Kehoe of the Ethyl Corporation. By the late 1960s, Lake Erie was declared dead and the Cuyahoga River briefly caught fire, and the American public had had enough. Earth Day happened in 1970, the EPA was founded in 1971, and here we are.

Support the show

Extract Knowledge
Listen elsewhere
Audio Apple
Published 2023-04-20

64: Like Groovy, Man

22 min
View

In this episode we hear of Robert and Joseph Switzer, brothers who invented fluorescent paints as college students in the 1930s, and parlayed it into an internationally famous business over the next few decades, till fluorescent paints and pigments became popular in the 1960s. The second half of the episode discusses the discovery of fluorescence and  how itworks, and we learn of the difference between fluorescence and phosphorescence.

Support the show

More description

In this episode we hear of Robert and Joseph Switzer, brothers who invented fluorescent paints as college students in the 1930s, and parlayed it into an internationally famous business over the next few decades, till fluorescent paints and pigments became popular in the 1960s. The second half of the episode discusses the discovery of fluorescence and  how itworks, and we learn of the difference between fluorescence and phosphorescence.

Support the show

Extract Knowledge
Listen elsewhere
Audio Apple
Published 2023-04-14

63: We Gotta Get Out of This Place

21 min
View

This episode's topic is World War II and later chemical warfare. Our first stop is with guest Dr. Mara Cohen Ioannides, to discuss Holocaust survivor, chemist, and writer Primo Levi, plus more. Then we learn of Louis Fieser's invention of napalm, which gained notoriety during the Vietnam War. After the Second World War, poisonous nerve compounds were under research in the UK, and we hear about the V-series of nerve agents. During the Vietnam War, Agent Orange was let loose, and we hear why it became a huge problem. Finally, we learn of the Soviet Union's invention of the Novichok nerve agent.

Support the show

More description

This episode's topic is World War II and later chemical warfare. Our first stop is with guest Dr. Mara Cohen Ioannides, to discuss Holocaust survivor, chemist, and writer Primo Levi, plus more. Then we learn of Louis Fieser's invention of napalm, which gained notoriety during the Vietnam War. After the Second World War, poisonous nerve compounds were under research in the UK, and we hear about the V-series of nerve agents. During the Vietnam War, Agent Orange was let loose, and we hear why it became a huge problem. Finally, we learn of the Soviet Union's invention of the Novichok nerve agent.

Support the show

Extract Knowledge
Listen elsewhere
Audio Apple
Published 2023-04-09

62: It is Rocket Science

22 min
View

We talk about rocketry from ancient times up through the early 1960s, concentrating on the chemistry, that is fuels to power rockets. We talk of the initial Chinese rockets and rocket-based toys and gimmicks created by ancient Greeks and Romans. We jump forward to the early 20th century and Konstantin Tsiolkovsky, who discussed possible rocket fuels for outer-space travel. We hear of the work of Robert Goddard and Hermann Oberth, and rocketry societies. The Nazis advanced rocketry to bring missiles, which sparked much interest in American and Soviet research during and after World War II. At this time, solid fuels began to be cast with polymers. We talk of various solid-fuel formulations, and liquid fuels as well. Finally, I mention a bit about ion-powered rockets.

Support the show

More description

We talk about rocketry from ancient times up through the early 1960s, concentrating on the chemistry, that is fuels to power rockets. We talk of the initial Chinese rockets and rocket-based toys and gimmicks created by ancient Greeks and Romans. We jump forward to the early 20th century and Konstantin Tsiolkovsky, who discussed possible rocket fuels for outer-space travel. We hear of the work of Robert Goddard and Hermann Oberth, and rocketry societies. The Nazis advanced rocketry to bring missiles, which sparked much interest in American and Soviet research during and after World War II. At this time, solid fuels began to be cast with polymers. We talk of various solid-fuel formulations, and liquid fuels as well. Finally, I mention a bit about ion-powered rockets.

Support the show

Extract Knowledge
Listen elsewhere
Audio Apple
Published 2023-03-31

61: Super Trouper

24 min
View

This episode discusses the controversy over the carbocation in organic chemistry in the 1950s, and experiments done to resolve the argument through the early 1960s, using superacids, especially in research by George Olah, William von Eggers Doering, and Lawrence H. Knox. We mention the main proponent, Saul Winstein and the main nay-sayer, Herbert Brown. We also take you through the basics of what a superacid is--and is not--and how dangerous superacids can be in the laboratory. Supporters of the podcast at Patreon can download a supplemental sheet with molecular structures.

Support the show

More description

This episode discusses the controversy over the carbocation in organic chemistry in the 1950s, and experiments done to resolve the argument through the early 1960s, using superacids, especially in research by George Olah, William von Eggers Doering, and Lawrence H. Knox. We mention the main proponent, Saul Winstein and the main nay-sayer, Herbert Brown. We also take you through the basics of what a superacid is--and is not--and how dangerous superacids can be in the laboratory. Supporters of the podcast at Patreon can download a supplemental sheet with molecular structures.

Support the show

Extract Knowledge
Listen elsewhere
Audio Apple
Published 2023-03-26

60: Join the Club

26 min
View

This episode concerns chemical societies: their history and value. We hear of the first scientific society in Rome, the slow spread of scientific societies, and the controversy over what was the first chemical society: in America, Scotland, or England? We learn of the first permanent chemical society, the Chemical Society of London, and its descendants, which now span the world. We hear of the reasons chemists have banded together to create such societies.

Support the show

More description

This episode concerns chemical societies: their history and value. We hear of the first scientific society in Rome, the slow spread of scientific societies, and the controversy over what was the first chemical society: in America, Scotland, or England? We learn of the first permanent chemical society, the Chemical Society of London, and its descendants, which now span the world. We hear of the reasons chemists have banded together to create such societies.

Support the show

Extract Knowledge
Listen elsewhere
Audio Apple
Published 2023-03-20

59: Don't Shoot the Messenger

23 min
View

In this episode, we talk about the mostly-forgotten OTHER nucleic acid, RNA, and the history of its discovery. Along the way we encounter Jean Brachet, who discovered the first physiological difference from DNA: it was in the cell cytoplasm. Soon thereafter, Nazi-funded Joachim Hämmerling found that the cell nucleus had genetic information, which ruled out RNA. We take a curve into the new information theory and computers, and maybe how genetic information was coded into DNA. We end up with Kenneth McQuillen and the role of ribosomes in the late 1950s. Only then was RNA finally understood in its biochemical role. 

Support the show

More description

In this episode, we talk about the mostly-forgotten OTHER nucleic acid, RNA, and the history of its discovery. Along the way we encounter Jean Brachet, who discovered the first physiological difference from DNA: it was in the cell cytoplasm. Soon thereafter, Nazi-funded Joachim Hämmerling found that the cell nucleus had genetic information, which ruled out RNA. We take a curve into the new information theory and computers, and maybe how genetic information was coded into DNA. We end up with Kenneth McQuillen and the role of ribosomes in the late 1950s. Only then was RNA finally understood in its biochemical role. 

Support the show

Extract Knowledge
Listen elsewhere
Audio Apple
Published 2023-03-13

58: Smoke Signals

21 min
View

This episode brings us up to almost the creation of environmental chemistry. The first part tells of the 1947 explosion of the S.S. Grandcamp in Texas City, USA, and the contributory factors, plus the horrendous damage to the entire bay and nearby cities. The second is how Arie Haagen-Smit discovered the cause of Los Angeles smog in the early 1950s, and what efforts were made before and after his work to mitigate the smog. The third part talks of the 1958 Food Additives Amendment from the U.S. Food and Drug Administration, including the Delaney Clause, which led to the cranberry sauce scare of 1959.

Support the show

More description

This episode brings us up to almost the creation of environmental chemistry. The first part tells of the 1947 explosion of the S.S. Grandcamp in Texas City, USA, and the contributory factors, plus the horrendous damage to the entire bay and nearby cities. The second is how Arie Haagen-Smit discovered the cause of Los Angeles smog in the early 1950s, and what efforts were made before and after his work to mitigate the smog. The third part talks of the 1958 Food Additives Amendment from the U.S. Food and Drug Administration, including the Delaney Clause, which led to the cranberry sauce scare of 1959.

Support the show

Extract Knowledge
Listen elsewhere
Audio Apple
Published 2023-03-07

57: The Future is Plastics

24 min
View

This episode is devoted to plastics invented or commercialized in the 1950s. Our first stop is carbon fibers, which started with Joseph Swan in the 19th century, but came of age in the late 1950s with Roger Bacon. Polyurethanes were finally commercialized in the early 1950s by B.F. Goodrich and Baeyer. Polyimides, though invented in 1908, weren't sold as products till the DuPont version, Kapton, in the 1950s. Poly(vinyl)alcohols came of age in 1950s as well, first by Japanese firm Kuraray in 1950, and now are ubiquitous in our society. Acrylonitrile-butadiene-styrene, or ABS, and similar copolymers, are also well-known from the 1950s onward--including the famous LEGO block. Spandex, or elastane, from DuPont in the 1950s, is popular in clothing as an improvement to latex rubber. Polycarbonate, first created in 1898, re-emerged in the 1950s jointly by General Electric and Baeyer. Polyacetals, from DuPont in the 1950s, are now found in kitchenware, car parts, and medical devices. Fluoroelastomers, elastic molecules with fluorine atoms, also date from the 1950s.

Support the show

More description

This episode is devoted to plastics invented or commercialized in the 1950s. Our first stop is carbon fibers, which started with Joseph Swan in the 19th century, but came of age in the late 1950s with Roger Bacon. Polyurethanes were finally commercialized in the early 1950s by B.F. Goodrich and Baeyer. Polyimides, though invented in 1908, weren't sold as products till the DuPont version, Kapton, in the 1950s. Poly(vinyl)alcohols came of age in 1950s as well, first by Japanese firm Kuraray in 1950, and now are ubiquitous in our society. Acrylonitrile-butadiene-styrene, or ABS, and similar copolymers, are also well-known from the 1950s onward--including the famous LEGO block. Spandex, or elastane, from DuPont in the 1950s, is popular in clothing as an improvement to latex rubber. Polycarbonate, first created in 1898, re-emerged in the 1950s jointly by General Electric and Baeyer. Polyacetals, from DuPont in the 1950s, are now found in kitchenware, car parts, and medical devices. Fluoroelastomers, elastic molecules with fluorine atoms, also date from the 1950s.

Support the show

Extract Knowledge
Listen elsewhere
Audio Apple
Published 2023-03-01

56: Chill Pill

21 min
View

We hear about the age of discovery of hormones and antibiotics, from the 1930s to the 1950s. Russell Marker left Penn State to find a plant from which to synthesize progesterone, so we learn about the trials and tribulations of the Mexican firm Syntex. Carl Djerassi joined Syntex and invented norethindrone. We learn of more fungal- and bacterial-based antibiotics, from streptomycin to tetracyclines, vancomycin, and methicillin--and what MRSA is.

Support the show

More description

We hear about the age of discovery of hormones and antibiotics, from the 1930s to the 1950s. Russell Marker left Penn State to find a plant from which to synthesize progesterone, so we learn about the trials and tribulations of the Mexican firm Syntex. Carl Djerassi joined Syntex and invented norethindrone. We learn of more fungal- and bacterial-based antibiotics, from streptomycin to tetracyclines, vancomycin, and methicillin--and what MRSA is.

Support the show

Extract Knowledge
Listen elsewhere
Audio Apple
Published 2023-02-23

55: Fab Four

25 min
View

We focus on the Group 4 elements: carbon (as an inorganic element), silicon, germanium--and a teeny bit about tin. We hear of the new mineral moissanite and Henri Moissan, about the race to synthesize diamonds with Tracy Hall, the weird properties of semiconductors found in the 19th and early 20th centuries, the first semiconductor device by Jagdish Chandra Bose, and quantum-mechanical explanations. We reach the production of the first transistors in the early 1950s--and how they got their name from John Pierce.

Support the show

More description

We focus on the Group 4 elements: carbon (as an inorganic element), silicon, germanium--and a teeny bit about tin. We hear of the new mineral moissanite and Henri Moissan, about the race to synthesize diamonds with Tracy Hall, the weird properties of semiconductors found in the 19th and early 20th centuries, the first semiconductor device by Jagdish Chandra Bose, and quantum-mechanical explanations. We reach the production of the first transistors in the early 1950s--and how they got their name from John Pierce.

Support the show

Extract Knowledge
Listen elsewhere
Audio Apple
Published 2023-02-17

54: Talkin' 'bout a Revolution

22 min
View

This episode is about the practical changes that appeared during the middle of the 20th century in chemistry laboratories. These are infrared spectrometers, pH meters, visible-ultraviolet spectrophotometers, mass spectrometers, nuclear magnetic resonance instruments, and chromatographs. All of these electronic instruments made the laboratory of the 1960s a most different place than the laboratory of the 1920s. We hear about some of the people who invented and promoted the use of these new chemical tools.

Support the show

More description

This episode is about the practical changes that appeared during the middle of the 20th century in chemistry laboratories. These are infrared spectrometers, pH meters, visible-ultraviolet spectrophotometers, mass spectrometers, nuclear magnetic resonance instruments, and chromatographs. All of these electronic instruments made the laboratory of the 1960s a most different place than the laboratory of the 1920s. We hear about some of the people who invented and promoted the use of these new chemical tools.

Support the show

Extract Knowledge
Listen elsewhere
Audio Apple
Published 2023-02-12

53: Beads on a String

21 min
View

This episode discusses the mid-20th-century discovery of the structure of proteins. We discuss Mikhail Tsvet's invention of chromatography and Frederick Sanger's revealing of the specific sequence of amino acids in proteins. Then we hear of Vincent du Vigneaud's synthesis of oxytocin and vasopressin, both small proteins. Max Perutz's work on adding heavy metals to proteins to get x ray diffraction helped scientists figure out protein structures. John Kendrew then used a digital computer to extract a structure from an x ray diffraction image. Finally we learn about Christian Anfinsen's work on protein folding and thermodynamics of folding.

Support the show

More description

This episode discusses the mid-20th-century discovery of the structure of proteins. We discuss Mikhail Tsvet's invention of chromatography and Frederick Sanger's revealing of the specific sequence of amino acids in proteins. Then we hear of Vincent du Vigneaud's synthesis of oxytocin and vasopressin, both small proteins. Max Perutz's work on adding heavy metals to proteins to get x ray diffraction helped scientists figure out protein structures. John Kendrew then used a digital computer to extract a structure from an x ray diffraction image. Finally we learn about Christian Anfinsen's work on protein folding and thermodynamics of folding.

Support the show

Extract Knowledge
Listen elsewhere
Audio Apple
Published 2023-02-05

52: Making It

19 min
View

We look at the progress organic chemist Robert Woodward achieved in the 20th century in organic synthesis, that is, creating from scratch all sorts of natural products. His first success was during World War II in synthesizing quinine. Then he was able to create strychnine, cholesterol, cortisone, lysergic acid, reserpine, chlorophyll, cephalosporin, and colchicine. These syntheses took a dozen to two dozen separate chemical reactions. His pinnacle of synthesis was the 1972 co-creation of Vitamin B12. We look at one of the most important mid-20th-century theoretical results of his work: the Woodward-Hoffman rules, co-invented with Holocaust survivor Roald Hoffman. Patreon supporters can download a supplemental sheet to show some diagrams of these molecules.

Support the show

More description

We look at the progress organic chemist Robert Woodward achieved in the 20th century in organic synthesis, that is, creating from scratch all sorts of natural products. His first success was during World War II in synthesizing quinine. Then he was able to create strychnine, cholesterol, cortisone, lysergic acid, reserpine, chlorophyll, cephalosporin, and colchicine. These syntheses took a dozen to two dozen separate chemical reactions. His pinnacle of synthesis was the 1972 co-creation of Vitamin B12. We look at one of the most important mid-20th-century theoretical results of his work: the Woodward-Hoffman rules, co-invented with Holocaust survivor Roald Hoffman. Patreon supporters can download a supplemental sheet to show some diagrams of these molecules.

Support the show

Extract Knowledge
Listen elsewhere
Audio Apple
Published 2023-01-30

51: Let's Take a Field Trip

22 min
View

We learn about developments in 20th-century theoretical inorganic chemistry, starting with coordination complexes as explained by Christian Blomstrand, Sophus Jørgensen, and Alfred Werner. Theory from a quantum-chemical perspective began with Jean Becquerel and Hans Bethe and "Crystal Field Theory." We then look at John Griffith and Leslie Orgel's "Ligand Field Theory." From classical complexes and their multitude of shapes, we move to organometallic complexes and bioinorganic complexes. The last topic of the episode is the discovery of ferrocene in 1951, and the weird shape the molecule has.

Support the show

More description

We learn about developments in 20th-century theoretical inorganic chemistry, starting with coordination complexes as explained by Christian Blomstrand, Sophus Jørgensen, and Alfred Werner. Theory from a quantum-chemical perspective began with Jean Becquerel and Hans Bethe and "Crystal Field Theory." We then look at John Griffith and Leslie Orgel's "Ligand Field Theory." From classical complexes and their multitude of shapes, we move to organometallic complexes and bioinorganic complexes. The last topic of the episode is the discovery of ferrocene in 1951, and the weird shape the molecule has.

Support the show

Extract Knowledge
Listen elsewhere
Audio Apple
Published 2023-01-24

50: This Mortal Coil

31 min
View

As a celebratory episode, reaching number 50 in this podcast, we talk about the history of DNA, from its discovery by Dr. Friedrich Miescher in the 1860s, to the race to uncover its correct structure in 1953, between the Great and Powerful Linus Pauling, and the less-great and certainly non-powerful James Watson and Francis Crick. Along the way, we learn of the fits and starts in figuring out what DNA's real function was, and how it differed from RNA (originally lumped together with DNA as "nucleic acid"). Among the scientists we find along the way are Frederick Griffith, Oswald Avery, Erwin Schrödinger, Erwin Chargaff, Edward Ronwin, Maurice Wilkins, Rosalind Franklin, and Peter Pauling.

Support the show

More description

As a celebratory episode, reaching number 50 in this podcast, we talk about the history of DNA, from its discovery by Dr. Friedrich Miescher in the 1860s, to the race to uncover its correct structure in 1953, between the Great and Powerful Linus Pauling, and the less-great and certainly non-powerful James Watson and Francis Crick. Along the way, we learn of the fits and starts in figuring out what DNA's real function was, and how it differed from RNA (originally lumped together with DNA as "nucleic acid"). Among the scientists we find along the way are Frederick Griffith, Oswald Avery, Erwin Schrödinger, Erwin Chargaff, Edward Ronwin, Maurice Wilkins, Rosalind Franklin, and Peter Pauling.

Support the show

Extract Knowledge
Listen elsewhere
Audio Apple
Published 2023-01-18

49: Hot Lead

21 min
View

In which we hear about 19th-century observations on the heat-capacity of gases, starting with Eunice Foot in 1856 and John Tyndall a few years later. Then we get to the first mathematical modeling of Earth's climate and how concentration of certain gases affects the climate, as done by Svante Arrhenius in 1896. Then we change to leaded gasoline in the 1920s, as promoted by General Motors and its employee, Thomas Midgely, Jr. Finally, we hear of the first of four pollution diseases of Japan, Itai-Itai, discovered in 1912 as a result of mining for silver in Toyama Prefecture, but only recognized as such a half-century later.

Support the show

More description

In which we hear about 19th-century observations on the heat-capacity of gases, starting with Eunice Foot in 1856 and John Tyndall a few years later. Then we get to the first mathematical modeling of Earth's climate and how concentration of certain gases affects the climate, as done by Svante Arrhenius in 1896. Then we change to leaded gasoline in the 1920s, as promoted by General Motors and its employee, Thomas Midgely, Jr. Finally, we hear of the first of four pollution diseases of Japan, Itai-Itai, discovered in 1912 as a result of mining for silver in Toyama Prefecture, but only recognized as such a half-century later.

Support the show

Extract Knowledge
Listen elsewhere
Audio Apple
Published 2023-01-12

48: Food for Thought

21 min
View

Once chemists realized that Staudinger was right, that molecules could be huge, protein research zoomed ahead. We hear of Gilbert Adair's study of hemoglobin, of the battle James Sumner had over the crystallization of urease with Richard Willstätter, and then the huge research William Astbury did on various keratin structures. Linus Pauling enters our story with his amazing work on the alpha-helix and beta-sheet generic forms that proteins take. Finally, Pauling announced in 1945 the first known genetic disease, sickle-cell anemia.

Support the show

More description

Once chemists realized that Staudinger was right, that molecules could be huge, protein research zoomed ahead. We hear of Gilbert Adair's study of hemoglobin, of the battle James Sumner had over the crystallization of urease with Richard Willstätter, and then the huge research William Astbury did on various keratin structures. Linus Pauling enters our story with his amazing work on the alpha-helix and beta-sheet generic forms that proteins take. Finally, Pauling announced in 1945 the first known genetic disease, sickle-cell anemia.

Support the show

Extract Knowledge
Listen elsewhere
Audio Apple
Published 2023-01-06

47: Good Vibrations

20 min
View

This episode is devoted to "spectroscopy," when you toss light at a sample and see how the sample responds. We talk of infrared spectroscopy, ultraviolet-visible spectroscopy, far-infrared spectroscopy, and microwaves. All of these types of light affect molecules--in different ways--and we learn how, and who was instrumental in developing each type.

Support the show

More description

This episode is devoted to "spectroscopy," when you toss light at a sample and see how the sample responds. We talk of infrared spectroscopy, ultraviolet-visible spectroscopy, far-infrared spectroscopy, and microwaves. All of these types of light affect molecules--in different ways--and we learn how, and who was instrumental in developing each type.

Support the show

Extract Knowledge
Listen elsewhere
Audio Apple
Published 2022-12-31

46: Polythene Pam

22 min
View

Here we start with more polymers popularized in the 1920s through the 1940s and beyond: polyvinyl chloride, or PVC, invented by accident in 1835 by Henri Regnault but made practical by Waldo Semon nearly a century later; polyethylene (polythene), invented by Hans von Pechmann, but commercialized by the mid- to late 1930s by ICI employees Eric Fawcett and Reginald Gibson; high-density polyethylene by a three separate teams in the early 1950s, causing a patent problem; acrylic by Rowland Hill, John Crawford, and Otto Röhm in 1933. On the inorganic side of polymers, Albert Ladenburg found the first silicone in 1871 but didn't quite understand it. Better knowledge came with Paul Kipping 30 years later and James Hyde 30 years after that. We end with polystyrene and polyethylene terephthalate (PET). Supporters of the podcast at Patreon can download a supplemental sheet to see the chemical structures of these materials.

Support the show

More description

Here we start with more polymers popularized in the 1920s through the 1940s and beyond: polyvinyl chloride, or PVC, invented by accident in 1835 by Henri Regnault but made practical by Waldo Semon nearly a century later; polyethylene (polythene), invented by Hans von Pechmann, but commercialized by the mid- to late 1930s by ICI employees Eric Fawcett and Reginald Gibson; high-density polyethylene by a three separate teams in the early 1950s, causing a patent problem; acrylic by Rowland Hill, John Crawford, and Otto Röhm in 1933. On the inorganic side of polymers, Albert Ladenburg found the first silicone in 1871 but didn't quite understand it. Better knowledge came with Paul Kipping 30 years later and James Hyde 30 years after that. We end with polystyrene and polyethylene terephthalate (PET). Supporters of the podcast at Patreon can download a supplemental sheet to see the chemical structures of these materials.

Support the show

Extract Knowledge
Listen elsewhere
Audio Apple
Published 2022-12-25

45: Mechanisms

23 min
View

Here we talk about mechanisms of organic reactions, that is, a physical model describing how particular organic molecules collide, interact, and react. The first chemist to discuss this in a modern way was Arthur Lapworth. We move to Robert Robinson, Arthur Michael, and then Irving Langmuir. Finally the current idea of a reaction mechanism was given by Christopher Ingold in the 1920s and 1930s. We talk of molecular symmetry and its relationship to reaction mechanisms.

Support the show

More description

Here we talk about mechanisms of organic reactions, that is, a physical model describing how particular organic molecules collide, interact, and react. The first chemist to discuss this in a modern way was Arthur Lapworth. We move to Robert Robinson, Arthur Michael, and then Irving Langmuir. Finally the current idea of a reaction mechanism was given by Christopher Ingold in the 1920s and 1930s. We talk of molecular symmetry and its relationship to reaction mechanisms.

Support the show

Extract Knowledge
Listen elsewhere
Audio Apple
Published 2022-12-19

44: Teflon Don

25 min
View

Today we examine the element fluorine and some ways it affected 20th-century chemistry. The first person to isolate the element was Henri Moissan in 1886, succeeding after many others failed, often with dangerous results. We talk about why fluorine is so reactive. Then we talk of Thomas Midgely's work at General Motors to invent the stable, non-toxic refrigerant Freon. We move to Roy Plunkett at DuPont, who discovered accidentally PTFE, a substance with a remarkably low coefficient of friction, which eventually led to the fabric Gore-Tex, and the fire-extinguishing compounds , the halons. We see how dentist Frederick McKay uncovered the cause of Colorado brown stain, and how fluoride ion protects teeth. We end up with some noble-gas compounds with fluorine, first discovered in 1962.

Support the show

More description

Today we examine the element fluorine and some ways it affected 20th-century chemistry. The first person to isolate the element was Henri Moissan in 1886, succeeding after many others failed, often with dangerous results. We talk about why fluorine is so reactive. Then we talk of Thomas Midgely's work at General Motors to invent the stable, non-toxic refrigerant Freon. We move to Roy Plunkett at DuPont, who discovered accidentally PTFE, a substance with a remarkably low coefficient of friction, which eventually led to the fabric Gore-Tex, and the fire-extinguishing compounds , the halons. We see how dentist Frederick McKay uncovered the cause of Colorado brown stain, and how fluoride ion protects teeth. We end up with some noble-gas compounds with fluorine, first discovered in 1962.

Support the show

Extract Knowledge
Listen elsewhere
Audio Apple
Published 2022-12-13

43: Elemental Masters

26 min
View

Here we learn about how scientists in the early 20th Century gradually became able to create isotopes, convert transmute elements from one to another, and eventually the invention of new, artificial isotopes not found in nature, such as phosphorus-31. We hear of tritium and carbon-14. Then we get to George Hevesy and his idea of radioactive tracing, including a prank he pulled on his landlady. Finally we get to scientists filling in the last gaps (unknown, undiscovered elements) up to uranium on the periodic table by the mid-1940s.

Support the show

More description

Here we learn about how scientists in the early 20th Century gradually became able to create isotopes, convert transmute elements from one to another, and eventually the invention of new, artificial isotopes not found in nature, such as phosphorus-31. We hear of tritium and carbon-14. Then we get to George Hevesy and his idea of radioactive tracing, including a prank he pulled on his landlady. Finally we get to scientists filling in the last gaps (unknown, undiscovered elements) up to uranium on the periodic table by the mid-1940s.

Support the show

Extract Knowledge
Listen elsewhere
Audio Apple
Published 2022-12-07

42: The Shape of You

21 min
View

By the late 1920s, scientists realized that electrons cannot be precisely located around atoms. The best we can do is describe the shape of the probability volume electrons take around atoms. Linus Pauling in the 1930s then took these shapes, and used to them to describe electrons' probability shapes around whole molecules with valence bond theory, explaining why molecules have the shapes they do. We also talk about molecular orbital theory, and how it usually--but not always--agrees with hybridization theory. Patreon subscribers get a supplemental sheet with diagrams.

Support the show

More description

By the late 1920s, scientists realized that electrons cannot be precisely located around atoms. The best we can do is describe the shape of the probability volume electrons take around atoms. Linus Pauling in the 1930s then took these shapes, and used to them to describe electrons' probability shapes around whole molecules with valence bond theory, explaining why molecules have the shapes they do. We also talk about molecular orbital theory, and how it usually--but not always--agrees with hybridization theory. Patreon subscribers get a supplemental sheet with diagrams.

Support the show

Extract Knowledge
Listen elsewhere
Audio Apple
Published 2022-12-01

41: By Land and by Air

20 min
View

Before environmental chemistry, there were definitely observations about Earth's environment and the part chemistry played. We start with Joseph Priestley and Jan Ingenhousz's observations on how plants and animals add to or remove oxygen from the air, and exchange the oxygen with carbon dioxide, in the 1770s. We then look at Théodore de Saussure, Adolphe-Théodore Brongniart, Jacques-Joseph Ébelmen, Jean Baptiste Boussingault, Eduard Suess, and Vladimir Vernadsky's work to understand the carbon cycle. For the nitrogen cycle, we turn to Boussingault, John Bennet Lawes, Joseph Henry Gilbert, Jules Reiset, Theophile Schlœsing, Achille Müntz, Ulysse Gayon, Gabriel Dupetit, Ulysse Gayon, Gabriel Dupetit, and Engelbert Broda's research on the nitrogen cycle. (It takes a whole biosphere to understand a biosphere.) Other observations about chemistry and the environment include Robert Angus Smith and acid rain, plus the ancient-to-modern knowledge of lead poisoning.

Support the show

More description

Before environmental chemistry, there were definitely observations about Earth's environment and the part chemistry played. We start with Joseph Priestley and Jan Ingenhousz's observations on how plants and animals add to or remove oxygen from the air, and exchange the oxygen with carbon dioxide, in the 1770s. We then look at Théodore de Saussure, Adolphe-Théodore Brongniart, Jacques-Joseph Ébelmen, Jean Baptiste Boussingault, Eduard Suess, and Vladimir Vernadsky's work to understand the carbon cycle. For the nitrogen cycle, we turn to Boussingault, John Bennet Lawes, Joseph Henry Gilbert, Jules Reiset, Theophile Schlœsing, Achille Müntz, Ulysse Gayon, Gabriel Dupetit, Ulysse Gayon, Gabriel Dupetit, and Engelbert Broda's research on the nitrogen cycle. (It takes a whole biosphere to understand a biosphere.) Other observations about chemistry and the environment include Robert Angus Smith and acid rain, plus the ancient-to-modern knowledge of lead poisoning.

Support the show

Extract Knowledge
Listen elsewhere
Audio Apple
Published 2022-11-25

40: Chain Gang

25 min
View

In this episode, we look at the rise of the Age of Plastics, with polymers from the 1920s and 1930s. We start with urea-formaldehyde resin from 1919, but before the true nature of polymers was clarified. We hear of Hermann Staudinger, who promoted the idea of macromolecules in the 1920s against significant resistance from European chemists. Thé Svedberg's ultracentrifuge gave credence to macromolecules. The rise of DuPont in the 1920s gave us the work of Wallace Carothers and his polymer group, which invented neoprene rubber, polyamide, the first polyester, and ultimately nylon. We learn of the simultaneous work by murderous firm I.G. Farben on synthetic rubbers to free Germany from dependence on latex: Buna, Buna-S, and Buna-N. We learn about hydrogen bonding, a discovery by an undergraduate, Maurice Huggins. 
Patreon subscribers have access to a supplemental sheet with molecular structures.

Support the show

More description

In this episode, we look at the rise of the Age of Plastics, with polymers from the 1920s and 1930s. We start with urea-formaldehyde resin from 1919, but before the true nature of polymers was clarified. We hear of Hermann Staudinger, who promoted the idea of macromolecules in the 1920s against significant resistance from European chemists. Thé Svedberg's ultracentrifuge gave credence to macromolecules. The rise of DuPont in the 1920s gave us the work of Wallace Carothers and his polymer group, which invented neoprene rubber, polyamide, the first polyester, and ultimately nylon. We learn of the simultaneous work by murderous firm I.G. Farben on synthetic rubbers to free Germany from dependence on latex: Buna, Buna-S, and Buna-N. We learn about hydrogen bonding, a discovery by an undergraduate, Maurice Huggins. 
Patreon subscribers have access to a supplemental sheet with molecular structures.

Support the show

Extract Knowledge
Listen elsewhere
Audio Apple
Published 2022-11-20

39: This Means War

22 min
View

We examine the first "chemical war," The Great War, or World War I, and its aftermath, and what made it so. Chlorine gas, phosgene gas, mustard gas, and Lewisite were the products of this era. We also discuss the chemical and political career of Chaim Weizmann, the "father of industrial fermentation," and the checkered history of Fritz Haber. Two decades after the Great War, the Nazis invented nerve agents, and used a pesticide to exterminate millions of people.

Support the show

More description

We examine the first "chemical war," The Great War, or World War I, and its aftermath, and what made it so. Chlorine gas, phosgene gas, mustard gas, and Lewisite were the products of this era. We also discuss the chemical and political career of Chaim Weizmann, the "father of industrial fermentation," and the checkered history of Fritz Haber. Two decades after the Great War, the Nazis invented nerve agents, and used a pesticide to exterminate millions of people.

Support the show

Extract Knowledge
Listen elsewhere
Audio Apple
Published 2022-11-13

38: Same but Different

22 min
View

This episode introduces isotopes, first understood by Frederick Soddy, while studying decays of radioactive elements. Then we look at half-lives of elements, first calculated by Ernest Rutherford. This led to the first reasonable age of the Earth, calculated by Bertram Boltwood. Soddy and Kasimir Fajans independently figure out what happens to isotopes vis-a-vis the periodic table. Stefanie Horovitz first proves the existence of isotopes after tedious lab work to isolate two forms of lead. Soon after, J.J. Thompson builds a crude mass spectrometer and distinguishes two forms of neon. We discuss isotopes of uranium and hydrogen.

Support the show

More description

This episode introduces isotopes, first understood by Frederick Soddy, while studying decays of radioactive elements. Then we look at half-lives of elements, first calculated by Ernest Rutherford. This led to the first reasonable age of the Earth, calculated by Bertram Boltwood. Soddy and Kasimir Fajans independently figure out what happens to isotopes vis-a-vis the periodic table. Stefanie Horovitz first proves the existence of isotopes after tedious lab work to isolate two forms of lead. Soon after, J.J. Thompson builds a crude mass spectrometer and distinguishes two forms of neon. We discuss isotopes of uranium and hydrogen.

Support the show

Extract Knowledge
Listen elsewhere
Audio Apple
Published 2022-11-07

37: Come to the Lab

23 min
View

We take a break from chemical observations and theory, and switch to practice. That is, we learn about the origins of the chemical laboratory in the Renaissance, and track its development up through the early 20th century. We see the switch from furnaces to gas lines for individual heating apparatuses. We see the start of ventilation, and the differentiation of experimental, lecture, and teaching laboratories. Gradually plumbing enters laboratories, and the arrangement of tables and benches becomes standardized. Laboratories even filter down into governmental school settings.

Support the show

More description

We take a break from chemical observations and theory, and switch to practice. That is, we learn about the origins of the chemical laboratory in the Renaissance, and track its development up through the early 20th century. We see the switch from furnaces to gas lines for individual heating apparatuses. We see the start of ventilation, and the differentiation of experimental, lecture, and teaching laboratories. Gradually plumbing enters laboratories, and the arrangement of tables and benches becomes standardized. Laboratories even filter down into governmental school settings.

Support the show

Extract Knowledge
Listen elsewhere
Audio Apple
Published 2022-11-01

36: An Oily Character

25 min
View

Here we talk a bit about the history of petroleum from ancient days to modernity. Among the moderns we hear of are Abraham Gesner, promoter of kerosene; Samuel Kier, huckster, canal-boat owner, and refiner; and Edwin Drake's well that ushered in the modern oil industry. We discuss fractional distillation of petroleum to isolate the various components, octane rating for fuels, and various international terms for "gasoline". Finally, we learn of hydrocarbons as lubricants, and I bring in Elliott Greenfield, Senior Engineer at Greenfield Manufacturing, to discuss physical properties of hydrocarbons.

Support the show

More description

Here we talk a bit about the history of petroleum from ancient days to modernity. Among the moderns we hear of are Abraham Gesner, promoter of kerosene; Samuel Kier, huckster, canal-boat owner, and refiner; and Edwin Drake's well that ushered in the modern oil industry. We discuss fractional distillation of petroleum to isolate the various components, octane rating for fuels, and various international terms for "gasoline". Finally, we learn of hydrocarbons as lubricants, and I bring in Elliott Greenfield, Senior Engineer at Greenfield Manufacturing, to discuss physical properties of hydrocarbons.

Support the show

Extract Knowledge
Listen elsewhere
Audio Apple
Show details
Episodes
187
Transcripts
0
0% coverage
Missing transcripts
187
With chapters
0