4. Thales (600 B.C.)
Water

5. Xenophanes (500 B.C.)
Earth
Water

6. Empedocles (440 B.C.) Four elements (more commonly called dirt)
Earth
(more commonly called dirt)
Water
Fire
Air

8. Two Forces shape matter
Love & Strife
2 minutes from athens to here

9. 9:19

10. Democritus Athens, Greece 400 B.C.

15. “Atoms” cannot be destroyed, so there is conservation of matter.
The smallest particles of matter are indivisible.
Since atomos is the Greek word for “indivisible” I shall call these particles “atoms”.
“Atoms” cannot be destroyed, so there is conservation of matter.

16. Aristotle Athens, Greece 340 B.C.
Aristotle studied under Plato who also had opinions on chemistry. However, Aristotle had the most influence on the history of chemistry.
9:21 end from sunflower. To change figure 45 seconds.
Besides chemistry, he also tackled physics, biology, psychology, and logic.

17. It’s ironic that the theories of Aristotle which were most accepted were also the most incorrect.
For example, he proposed and embraced the mystical fifth element. It took chemists 2,000 years to recognize that there was no mystical fifth element.
His theories that were most correct were mostly ignored.
For example, he correctly classified dolphins as mammals and not fish. It took 2,000 years for biologists to accept this.

18. First Table of the Elements
Hot
Dry
9:22
Cold
Wet

19. Fifth Element
Quintessence
Philosopher’s stone

20. Fifth Element makes up the celestial bodies
Gold is the perfect metal. All other metals are less perfect.
The fifth element is so divine that it can turn the lesser (more base) metals into gold.

21. Elixir of life (a fountain of youth)
Fifth Element
Elixir of life (a fountain of youth)

22. Disagree with Democritus
Matter does not consist of atoms
Democritus said atoms cannot be divided. You cannot place restraints on the gods.

23. Antoine Laurent Lavoisier France 1793
Lavoisier has been called the father of modern chemistry.
Started a system of chemical nomenclature that used ide, -ic & -ous endings.
9:54:35
He observed that birds lived longer in the new "eminently respirable air," as he described it, and he showed that this air combined with carbon to produce the "fixed air" (carbon dioxide) obtained by Joseph Black in 1754.
Examples: Sodium chloride, Ferric oxide and Ferrous oxide

24. Antoine married the daughter of the tax collector, which helped him pay for his expensive laboratory.
Marie acted as a skilled lab assistant, translator of English science publications, and illustrator for Lavoisier’s experiments

25. Lavoisier
When heated mercury turned red and absorbed 1/5 of the air.
The amount of “active air” consumed was the same as the amount of “active air” released later.
1 5
9:56
Lavoisier Searches For The Lost Air
Priestley had already settled at Calne but had not yet made his famous experiment on orange-red mercurius calcinatus when the events that are about to be related took place. The scene was the top story of a house in a residential district of Paris, a place that had been turned into a large laboratory. On the morning when our story opens, Antoine Lavoisier was occupied with a minor experiment. Marie Anne Lavoisier, his vivacious blue-eyed wife, was busy at her work table that was littered
with papers. She was his laboratory assistant and the official illustrator for his scientific publications. She had been translating into French, for her husband's benefit, some reports from the proceedings of the British Royal Society. The one in her hand
related to the heating of tin in a closed flask as reported by Robert Boyle. (We have already told about Boyle's findings.) The
work had been carried out almost a century before, but it was new to the Lavoisiers. She had sketched quickly the
arrangement of the apparatus that Boyle said he had used.
As she finished with her sketching, her husband sat down beside her, picked up the sheets of paper and the sketches, and
glanced over them. Then he looked again, more closely. "Interesting! So Boyle found that the tin gained in weight when
heated, but could not determine the source of the added weight! Well he must have missed something. We shall have to
repeat that experiment to see what it is." So, in almost a casual way, an experiment was begun that was to change the history
of chemistry. But before putting the results down we shall need to say something about the scientist himself.
Lavoisier came from a family of a rich merchant, and no expense had been spared in his education. He was a very able
student, distinguishing himself in mathematics and science. At twenty he was in correspondence with virtually all the
outstanding men of mathematics and science in France. At twenty-two he presented a paper on the analysis of gypsum before
the Academy of Sciences at Paris. Also in that same year he received a gold medal from the King of France for a detailed
report on the best way to light the streets of Paris at night. At twenty-five he was elected to membership in the French
Academy. Within the next three years he presented scientific papers to the Academy on such diverse topics as divining rods,
hypnotism, the construction of chairs for invalids, methods of ensuring a wholesome drinking-water supply for Paris, and the
need for fire hydrants on city streets.
Also, at the age of twenty-five he bought a share in the Farmers General, a corporation with wide financial dealings. The share cost close to one and a half million francs, for which his father furnished most of the money. The investment seemed desirable, for each share was paying, in dividends, about a hundred thousand francs a year. In short time he was more than a mere stockholder. The corporation had been granted a license to produce, at a specified cost, the gunpowder for the French Army.
There had been some complaint about the quality of the product, and officials of the Farmers General commissioned Lavoisier, as a chemist, to supervise the work and to make suggestions for improvement. He was successful in making the French gunpowder the best in Europe—though not the cheapest.
When he was twenty-eight he met the petite teen-age daughter of a wealthy member of the Farmers General. He and Marie Anne Paulze were married in 1771 and lived in a house given to them as a wedding present. The top story of this house was remodeled into a spacious laboratory. Here is a comment about young Madame Lavoisier that was jotted down in his diary
by an Englishman who visited briefly in the home: "A lively, sensible, scientific lady, a woman of understanding, that works with her husband in the laboratory, who knows how, by her presence and conversation, to adorn the best repast."5 As for
Lavoisier himself, most people liked the brilliant young man. He had several close friends who were in and out of the laboratory checking to see how matters were going. But there were some in the Academy who disliked him. There was
jealousy over his rapid advancement; there was criticism over his wealthy connections. Some objected to giving high posts to
one who was not a member of the aristocracy. One member hated him bitterly because Lavoisier had calmly accused him of
using unethical business practices. Another accused Lavoisier of claiming that he was the first to analyze gypsum, thus taking
honor from the rightful claimant.
People did not question his ability. But there were few scientists in those days who agreed with his ideas about chemistry. He
considered that an element in shifting from one compound to another took its weight along, so a chemical change could make
no change in total weight. This was difficult to prove.
Now we are back to the experiments on the heating of tin in a closed flask. Lavoisier followed Boyle's plan, except that he
selected a larger flask and sealed the flask with the tin in it tightly before applying any heat. He saw that as the heating took
place the grayish-white calx appeared on the surface of the melted tin; this was exactly as Boyle had described. He continued
the heating for a day and a half, then allowed the flask to cool; this was just what Boyle had done. He weighed the calx and
saw that it was heavier than the tin from which it had been formed; this was the same result that Boyle had found. But
Lavoisier made two additional weighings. He weighed the sealed flask before it was heated and after it was heated. Those
weights were exactly the same. The tin, then, had gained in weight, but the closed-in flask had not lost any. The weight gained must have come from the air in the flask. Part of the air was gone. When the flask was opened some outside air had rushed in to take the place of the air that was lost.
The argument appeared correct; the conclusions seemed without fault. Lavoisier repeated the experiment, however, several
times to make sure of every point. In one particular case the flask was unsealed under water. Water came in, and filled the
flask one-fifth full. So the lost air was one-fifth of all the air that had been in the flask. The full experiment seemed now
complete and might be set aside. But a few questions kept coming to his mind. Apparently common air is a mixture of two
colorless, odorless gases that can be distinguished by their behavior toward heated tin. He had discovered that the active air
made up a fifth of the total, but, in a way, he had not discovered the gas itself. He had never collected it in a bottle or tested it.
Perhaps it would appear premature to send a report about his finding and conclusions to the Academy of Sciences unless he
knew more about the active air.
Lavoisier sent a terse report of his experiments and findings (not mentioning Boyle's previous work) to the Academy with the
notation on the outside of the communication that it was to be placed in the files unopened until he asked for its release. Since
he had been accused of claiming to have been the discoverer of an analysis method for gypsum though another had found it
first, in this case he was establishing a claim of priority with his dated communication. He told his wife about seeing a smelter
get tin from tin ore by the heat of the smelter's furnace. He thought he would try the effect of intense heat on the calx of tin
they had been making. If the heat drove off the active air, to leave the tin behind, that air could be collected and studied. The
idea might be worth trying. He set up a simple arrangement and fanned the fire with the air from a bellows; nothing happened.
He tried again, using the red-brown calx of iron; no gas. Then he used the yellowish calx of lead; no gas. He concluded that
his idea had not been a good one.
But not long after this something occurred that changed his mind. Joseph Priestley came as a visitor to Paris, and Lavoisier
and his wife attended a dinner meeting of scientists at which the English scientist spoke briefly of a discovery, not yet
published, that he had made of a strange and wonderful gas formed by the heating of orange-red mercurius calcinatus, the
calx of mercury. Lavoisier looked knowingly at his wife. He had not thought of trying the calx of mercury. This new gas of
Priestley's was probably the lost air for which he had been searching!
Early the next morning there was a hum of activity in the top-story laboratory. As soon as the apothecary shops were open, a
supply of the orange-red calx of mercury was hastily purchased. Lavoisier put a portion of it into a tube of special glass that
could stand strong heating. Drops of metallic mercury soon gathered on cool parts of the tube. That a gas was coming off was
not evident until a candle, as in Priestley's experiment, flared out with an enlarged flame when placed at the tube's mouth.
Lavoisier picked up an old book on chemistry and read that the calx of mercury formed slowly on the surface of boiling
mercury and that the vapor of mercury was very dangerous to breathe, often causing death. The statement suggested to him
that mercury could be used instead of tin to remove active air from ordinary air. Then the calx of mercury that had been
formed could be heated to get the active air back again. He wanted to try that!
The arrangement of equipment took some planning. Lavoisier put some mercury into a large glass retort that could be set over a slow fire. The open end of the retort he bent up into a reservoir of air set over a supply of mercury. He kept the heating slow and steady, holding the temperature to a point where the mercury was agitated gently as it boiled. Gradually, very gradually, he saw a thin layer of orange-red powder form on the mercury surface. As the amount of this powder increased, some of the air in the reservoir was lost. In time, he stopped the experiment. He collected and weighed the powder, and determined the volume of the air that was lost. Now he reversed the process. He transferred the powder to a glass tube and
heated it strongly. The gas coming off he caught and measured. What were the results? He found that the mercury that had gone into the calx was returned to mercury again. There was no loss whatever. The active air used up in making the calx was back again. There was no loss whatever.
Lavoisier was now ready to have the seal broken on the communication to the Academy, and he had a new report to add to
it. He was ready to prove that air is a mixture of two colorless, odorless gases. He was ready to state that the forming of the
calx of mercury is the union of mercury and active air. Years later he would call the active air by the new name of oxygen. The
rest of the air was to be called nitrogen.

26. Lived longer Died quickly Lived for a while non-active Air Room Air
Oxygen
Azote
acids
Sulfuric acid
generate
S + O2  SO2
2SO2 + O2  2 SO3
SO3 + H2O  H2SO4
9:56
Lavoisier Searches For The Lost Air
Priestley had already settled at Calne but had not yet made his famous experiment on orange-red mercurius calcinatus when
the events that are about to be related took place. The scene was the top story of a house in a residential district of Paris, a
place that had been turned into a large laboratory. On the morning when our story opens, Antoine Lavoisier was occupied
with a minor experiment. Marie Anne Lavoisier, his vivacious blue-eyed wife, was busy at her work table that was littered
with papers. She was his laboratory assistant and the official illustrator for his scientific publications. She had been translating
into French, for her husband's benefit, some reports from the proceedings of the British Royal Society. The one in her hand
related to the heating of tin in a closed flask as reported by Robert Boyle. (We have already told about Boyle's findings.) The
work had been carried out almost a century before, but it was new to the Lavoisiers. She had sketched quickly the
arrangement of the apparatus that Boyle said he had used.
As she finished with her sketching, her husband sat down beside her, picked up the sheets of paper and the sketches, and
glanced over them. Then he looked again, more closely. "Interesting! So Boyle found that the tin gained in weight when
heated, but could not determine the source of the added weight! Well he must have missed something. We shall have to
repeat that experiment to see what it is." So, in almost a casual way, an experiment was begun that was to change the history
of chemistry. But before putting the results down we shall need to say something about the scientist himself.
Lavoisier came from a family of a rich merchant, and no expense had been spared in his education. He was a very able
student, distinguishing himself in mathematics and science. At twenty he was in correspondence with virtually all the
outstanding men of mathematics and science in France. At twenty-two he presented a paper on the analysis of gypsum before
the Academy of Sciences at Paris. Also in that same year he received a gold medal from the King of France for a detailed
report on the best way to light the streets of Paris at night. At twenty-five he was elected to membership in the French
Academy. Within the next three years he presented scientific papers to the Academy on such diverse topics as divining rods,
hypnotism, the construction of chairs for invalids, methods of ensuring a wholesome drinking-water supply for Paris, and the
need for fire hydrants on city streets.
Also, at the age of twenty-five he bought a share in the Farmers General, a corporation with wide financial dealings. The share
cost close to one and a half million francs, for which his father furnished most of the money. The investment seemed desirable,
for each share was paying, in dividends, about a hundred thousand francs a year. In short time he was more than a mere
stockholder. The corporation had been granted a license to produce, at a specified cost, the gunpowder for the French Army.
There had been some complaint about the quality of the product, and officials of the Farmers General commissioned
Lavoisier, as a chemist, to supervise the work and to make suggestions for improvement. He was successful in making the
French gunpowder the best in Europe—though not the cheapest.
When he was twenty-eight he met the petite teen-age daughter of a wealthy member of the Farmers General. He and Marie
Anne Paulze were married in 1771 and lived in a house given to them as a wedding present. The top story of this house was
remodeled into a spacious laboratory. Here is a comment about young Madame Lavoisier that was jotted down in his diary
by an Englishman who visited briefly in the home: "A lively, sensible, scientific lady, a woman of understanding, that works
with her husband in the laboratory, who knows how, by her presence and conversation, to adorn the best repast."5 As for
Lavoisier himself, most people liked the brilliant young man. He had several close friends who were in and out of the
laboratory checking to see how matters were going. But there were some in the Academy who disliked him. There was
jealousy over his rapid advancement; there was criticism over his wealthy connections. Some objected to giving high posts to
one who was not a member of the aristocracy. One member hated him bitterly because Lavoisier had calmly accused him of
using unethical business practices. Another accused Lavoisier of claiming that he was the first to analyze gypsum, thus taking
honor from the rightful claimant.
People did not question his ability. But there were few scientists in those days who agreed with his ideas about chemistry. He
considered that an element in shifting from one compound to another took its weight along, so a chemical change could make
no change in total weight. This was difficult to prove.
Now we are back to the experiments on the heating of tin in a closed flask. Lavoisier followed Boyle's plan, except that he
selected a larger flask and sealed the flask with the tin in it tightly before applying any heat. He saw that as the heating took
place the grayish-white calx appeared on the surface of the melted tin; this was exactly as Boyle had described. He continued
the heating for a day and a half, then allowed the flask to cool; this was just what Boyle had done. He weighed the calx and
saw that it was heavier than the tin from which it had been formed; this was the same result that Boyle had found. But
Lavoisier made two additional weighings. He weighed the sealed flask before it was heated and after it was heated. Those
weights were exactly the same. The tin, then, had gained in weight, but the closed-in flask had not lost any. The weight gained
must have come from the air in the flask. Part of the air was gone. When the flask was opened some outside air had rushed in
to take the place of the air that was lost.
The argument appeared correct; the conclusions seemed without fault. Lavoisier repeated the experiment, however, several
times to make sure of every point. In one particular case the flask was unsealed under water. Water came in, and filled the
flask one-fifth full. So the lost air was one-fifth of all the air that had been in the flask. The full experiment seemed now
complete and might be set aside. But a few questions kept coming to his mind. Apparently common air is a mixture of two
colorless, odorless gases that can be distinguished by their behavior toward heated tin. He had discovered that the active air
made up a fifth of the total, but, in a way, he had not discovered the gas itself. He had never collected it in a bottle or tested it.
Perhaps it would appear premature to send a report about his finding and conclusions to the Academy of Sciences unless he
knew more about the active air.
Lavoisier sent a terse report of his experiments and findings (not mentioning Boyle's previous work) to the Academy with the
notation on the outside of the communication that it was to be placed in the files unopened until he asked for its release. Since
he had been accused of claiming to have been the discoverer of an analysis method for gypsum though another had found it
first, in this case he was establishing a claim of priority with his dated communication. He told his wife about seeing a smelter
get tin from tin ore by the heat of the smelter's furnace. He thought he would try the effect of intense heat on the calx of tin
they had been making. If the heat drove off the active air, to leave the tin behind, that air could be collected and studied. The
idea might be worth trying. He set up a simple arrangement and fanned the fire with the air from a bellows; nothing happened.
He tried again, using the red-brown calx of iron; no gas. Then he used the yellowish calx of lead; no gas. He concluded that
his idea had not been a good one.
But not long after this something occurred that changed his mind. Joseph Priestley came as a visitor to Paris, and Lavoisier
and his wife attended a dinner meeting of scientists at which the English scientist spoke briefly of a discovery, not yet
published, that he had made of a strange and wonderful gas formed by the heating of orange-red mercurius calcinatus, the
calx of mercury. Lavoisier looked knowingly at his wife. He had not thought of trying the calx of mercury. This new gas of
Priestley's was probably the lost air for which he had been searching!
Early the next morning there was a hum of activity in the top-story laboratory. As soon as the apothecary shops were open, a
supply of the orange-red calx of mercury was hastily purchased. Lavoisier put a portion of it into a tube of special glass that
could stand strong heating. Drops of metallic mercury soon gathered on cool parts of the tube. That a gas was coming off was
not evident until a candle, as in Priestley's experiment, flared out with an enlarged flame when placed at the tube's mouth.
Lavoisier picked up an old book on chemistry and read that the calx of mercury formed slowly on the surface of boiling
mercury and that the vapor of mercury was very dangerous to breathe, often causing death. The statement suggested to him
that mercury could be used instead of tin to remove active air from ordinary air. Then the calx of mercury that had been
formed could be heated to get the active air back again. He wanted to try that!
The arrangement of equipment took some planning. Lavoisier put some mercury into a large glass retort that could be set over
a slow fire. The open end of the retort he bent up into a reservoir of air set over a supply of mercury. He kept the heating
slow and steady, holding the temperature to a point where the mercury was agitated gently as it boiled. Gradually, very
gradually, he saw a thin layer of orange-red powder form on the mercury surface. As the amount of this powder increased,
some of the air in the reservoir was lost. In time, he stopped the experiment. He collected and weighed the powder, and
determined the volume of the air that was lost. Now he reversed the process. He transferred the powder to a glass tube and
heated it strongly. The gas coming off he caught and measured. What were the results? He found that the mercury that had
gone into the calx was returned to mercury again. There was no loss whatever. The active air used up in making the calx was
back again. There was no loss whatever.
Lavoisier was now ready to have the seal broken on the communication to the Academy, and he had a new report to add to
it. He was ready to prove that air is a mixture of two colorless, odorless gases. He was ready to state that the forming of the
calx of mercury is the union of mercury and active air. Years later he would call the active air by the new name of oxygen. The
rest of the air was to be called nitrogen.

27. Table of the Elements (33)
Antimony
Arsenic
Bismuth
Cobalt
Copper
Gold
Iron
Lead
Manganese
Mercury
Molybdena
Nickel
Platina
Silver
Tin
Tungstein
Zinc
Oxygen
Azote
Hydrogen
Sulphur
Phosphorus
Charcoal
Muriatic radical
Fluoric radical
Boracic radical
Lime
Magnesia
Barytes
Argill
Silex
Argill (clay or alum=potassium aluminum sulfate)
Silex (silicon dioxide = quartz
Magnesia (epsom salts=magnesium sulfate)
Lime = calcium oxide

28. John Dalton England

29. Elements are composed of minute, indivisible particles called atoms

30. 4. Chemical compounds are formed by the union of two or more atoms of different elements.

31. 5. Atoms combine to form compounds in simple ratios, such as 1:1, 1:2, 2:2, 1:3, and so forth.

32. For example, if we decomposed 100 grams of water using electricity, we always get this proportion of mass.
88.8%
88.8 grams
Oxygen
11.2%
11.2 grams
Hydrogen

33. We call this: The Law of Multiple Proportions
6. Atoms of two elements may combine in different ratios to form more than one compound.
We call this: The Law of Multiple Proportions

34. Arranged from light to heavy by their relative weights
Dalton’s Elements

35. Johan Jacob Berzelius from Sweden

36. Berzelius’ Symbols for Elements
Older elements take the symbol from their Latin name.
Fe comes from ferrum not iron.
Instead of G for gold he wants Au from aurum.
Instead of S for Silver he wants Ag from argentum.
Newer symbols come from English names.
O comes from oxygen.
2000 experiments over a ten-year period to determine accurate atomic masses for all the elements now known.

37. John Newlands England
Researchers had already began to arrange and classify elements:
Metals vs. non-metals
In tables of increasing atomic weight
John Newlands from England had a different way to arrange elements.

38. I call this the “Law of Octaves”
Certain elements resembled one another in behavior.
Chlorine, bromine & iodine
violently corrosive
form acids
Lithium, sodium, potassium
Unite violently with oxygen or water
Oxides form caustic aqueous solutions
Every eighth element have similar characteristics
Li Be B C N O F
Na Mg Al Si P S Cl
K Ca ? ? As Se Br
I call this the “Law of Octaves”

39. Lightest to heaviest. Li
Be B C N O F
Na Mg Al Si P S Cl K
Ca ? ? As Se Br
A B C D E F G A B C D E F G A B C D E F G Li
Be B C N O F
Na Mg Al Si P S Cl K
Ca ? ? As Se Br
I call this the “Law of Octaves” because of its similarity to musical octaves

40. “Law of Octaves”
He presented his theory to the England Chemical Society and was laughed at.
They said to arrange it alphabetically.

41. Dmitri Ivanovich Mendeleev Russia 1871

42. Periodic Law
Like Newlands, he used the lithium, sodium, and potassium plus the chlorine family as guide posts
He also saw a periodic repeating of characteristics. However on the third period, he thought there were more than the seven elements that Newlands listed.

44. Gallium
Germanium

47. Periodic Table of the Elements
The elements are ordered by the number
of protons they have in their nucleus
Atomic Number

48. Periodic Table of the Elements Elements are listed by increasing mass.
But grouped by reoccuring properties

49. WHERE DID THE ELEMENTS COME FROM?

50. End