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The Mystery of Matter

Harry Moseley | Changing the Role of Scientists in War

In 1913, English graduate student Harry Moseley redefined the Periodic Table using X-rays to reveal the importance of atomic number — the number of protons in an atom’s nucleus. But when World War I broke out, Moseley enlisted and was killed by a sniper’s bullet in Turkey. His shocking death at age 27 forever changed the role of scientists during war.

Episodes of The Mystery of Matter3

Video thumbnail: The Mystery of Matter Into the Atom

The Mystery of Matter

Into the Atom

Find out how the creation of a new element changes the world forever.

55:19

Into the Atom

55:19

Video thumbnail: The Mystery of Matter Out of Thin Air

The Mystery of Matter

Out of Thin Air

See how Joseph Priestley & Antoine Lavoisier trigger a worldwide search for new elements.

54:20

Out of Thin Air

54:20

Video thumbnail: The Mystery of Matter Unruly Elements

The Mystery of Matter

Unruly Elements

Explore how the discovery of radioactivity changed how elements were understood.

53:50

Unruly Elements

53:50

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Clips of The Mystery of Matter8

Video thumbnail: The Mystery of Matter  Joseph Priestley | A Momentous Encounter

The Mystery of Matter

Joseph Priestley | A Momentous Encounter

See how Priestley’s friendship with Benjamin Franklin led to his own career in science.

3:55

Joseph Priestley | A Momentous Encounter

3:55

Video thumbnail: The Mystery of Matter Antoine Lavoisier | Lavoisier’s Better Half

The Mystery of Matter

Antoine Lavoisier | Lavoisier’s Better Half

Meet Marie Anne, Antoine Lavoisier’s young wife and most important collaborator.

4:17

Antoine Lavoisier | Lavoisier’s Better Half

4:17

Video thumbnail: The Mystery of Matter Carl Wilhelm Scheele | Discovering Fire Air

The Mystery of Matter

Carl Wilhelm Scheele | Discovering Fire Air

In this bonus clip, hear about a Swedish apothecary's role in the discovery of oxygen.

1:30

Carl Wilhelm Scheele | Discovering Fire Air

1:30

Video thumbnail: The Mystery of Matter Dmitri Mendeleev | The Element Mendeleev Never Accepted

The Mystery of Matter

Dmitri Mendeleev | The Element Mendeleev Never Accepted

Discover why radium was the one element whose properties Dmitri Mendeleev never accepted.

4:53

Dmitri Mendeleev | The Element Mendeleev Never Accepted

4:53

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Previews of The Mystery of Matter6

Video thumbnail: The Mystery of Matter First Look | Humphry Davy

The Mystery of Matter

First Look | Humphry Davy

See how Humphry Davy entered the search for new elements with by discovering laughing gas.

First Look | Humphry Davy

Video thumbnail: The Mystery of Matter First Look | Priestley & Lavoisier

The Mystery of Matter

First Look | Priestley & Lavoisier

Watch how the discovery of oxygen by this odd couple triggers the search for new elements.

First Look | Priestley & Lavoisier

Video thumbnail: The Mystery of Matter Next on Episode 2 | Dmitri Mendeleev

The Mystery of Matter

Next on Episode 2 | Dmitri Mendeleev

Follow the story of Dmitri Mendeleev's invention of the Periodic Table.

0:31

Next on Episode 2 | Dmitri Mendeleev

0:31

Video thumbnail: The Mystery of Matter Next on Episode 2 | Marie Curie

The Mystery of Matter

Next on Episode 2 | Marie Curie

Learn why the discovery of radioactivity shatters the order of the Periodic Table.

Next on Episode 2 | Marie Curie

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