Air-conditioning, refrigeration, and superconductivity are just some of the ways technology has put cold to use. But what is cold, how do you achieve it, and how cold can it get? We follow the quest for cold from Cornelius Drebbel up to Michael Faraday.
Questions: please answer the following in complete sentences, demonstrating that you understand the concepts involved.
In this show Andrew Szydlo, a well known chemistry professor, enjoys re-enacting the work of the great court magician & chemist, Cornelius Drebbel, 1600’s France.
1. How did Drebbel (likely) create the world’s first demonstration of indoor air conditioning?
Robert Boyle, famous for his study of gas, temperature and pressure. He systematically worked through a series of ideas about what cold is: Please answer:
2. Does cold come from the air? Is cold transferred by “frigorific” cold-making particles? If not, what does cold come from? How did Boyle show that “cold” was probably not a material?
The first temperature scale to be widely adopted was devised by Gabriel Daniel Fahrenheit. He was a gifted instrument maker who made thermometers for scientists and physicians across Europe.
3. How did he set his lowest temperature? How did he set his other reference temperatures?
In terms of temperature, is there an absolute lower limit? The idea that there might be one, would become a turning point in the history of cold. The story begins with the French physicist Guillaume Amontons. He was doing experiments heating and cooling bodies of air to see how they expand and contract.
4. How did Amotons realize that there must be a lowest possible temperature, an absolute zero? (Explain his reasoning.)
The science of cold was about to suffer a serious setback. A rival theory of heat and cold emerged that was appealing, yet wrong. It was called the caloric theory, and its principle advocate was the great French chemist Antoine Lavoisier, 1700s France. In so many ways he was brilliant, and his careful experiments created much of modern day Chemistry. Lavoisier even developed the theory of conservation of matter. But on the topic of heat and cold, he was mistaken.
5. According to Lavoisier, what was “caloric”? Also, why do you think it is possible for a brilliant scientist to be so correct in so many other areas of science, yet completely incorrect in another area? (This isn’t answered within the program. I am looking for your thoughts.)
One scientist was convinced that Lavoisier was wrong about caloric – and was determined to destroy the caloric theory. His name was Sir Benjamin Thompson, Count Rumford. (*) He was born in America, spied for the British during the Revolution, and after being forced into exile, became an influential government minister in Bavaria. Among his varied responsibilities was the artillery works, and it was here, in the 1790s, that he began to think about how he might be able to disprove the caloric theory.
6. How did he show that heat was not a fluid or material? In Count Rumford’s view, what was heat?
(*) Although his name was Ben Thompson, he is universally known as Count Rumford. What does that even mean? For his efforts in improving the life of people in the nation-state of Bavaria, he was made a Count of the Holy Roman Empire. Thompson took the name “Rumford” for Rumford, New Hampshire, the older name for the town of Concord.
Michael Faraday, who later became famous for his work on electricity and magnetism, would take a critical early step in the long descent towards absolute zero. He was asked to investigate the properties of chlorine using crystals of chlorine hydrate, in 1823.
Faraday took the sealed tube and heated the end containing the chlorine hydrate in hot water. He put the other end in an ice bath. Soon he noticed yellow chlorine gas being given off. Because the gas is being produced, pressure’s building up inside this glass tube!
When Faraday did the experiment, a visitor, Dr. Paris, came by to see what he was up to. Paris pointed out some oily matter in the bottom of the tube. Faraday was curious, and decided to break open the tube…. The explosion sent shards of glass flying. With the sudden release of pressure, the oily liquid vanished.
7. What did Faraday learn about heat, cold, gas and pressure, from this?