/kloc-Before the 0/8th century, the development of chemistry was extremely slow. Lavoisier lived in the middle and late18th century, and chemistry was only in the period of "collecting materials". People just regard it as a by-product of the pharmaceutical industry and call it a "maid". It is also a clumsy "maid".
At that time, it was generally believed that "water will turn to wood" and "water will turn to soil". Lavoisier is skeptical. He is determined to speak with facts and illustrate the problem with experiments.
He installed a large distillation bottle in his laboratory, then poured the cooled distilled water into a large flask, sealed the bottle mouth, weighed it, and heated it day and night on an alcohol lamp. After heating for 25 days, the water began to be turbid, solid particles appeared on 27 days, and sediment appeared in the bottle after 30 days. On this basis, people may think that "water can become soil". But lavoisier thinks this is an "illusion" after a calm analysis. After 30 days, he did not stop heating, but continued heating until the first day 100.
After stopping heating, lavoisier weighed the cooled flask and distilled water, and their weights were exactly the same as before heating, without any change. Then he weighed distilled water separately, as before heating. He also called muck and sediment, was it 1? 74 grams. When lavoisier turned to weigh the empty flask again, he was surprised to find that it was lighter than before heating 1? 74 grams!
"Long live the hundred-day experiment!" Lavoisier and his assistants cheered. This experiment obviously proves that the hypothesis that "water becomes soil" is incorrect, and the "soil" precipitated after water evaporation comes from the container instead of water.
People attach great importance to lavoisier's experiment, and the legendary viewpoint is constantly doubted by people. Scientists are competing to test the traditional theory with experiments.
At that time, there was an authoritative theory in society that matter could burn because it contained a phlogiston. When a substance burns, the phlogiston contained in it is exhausted. Even if the substance itself does not contain phlogiston, it can burn after absorbing phlogiston. The phlogiston theory has dominated the field of chemistry for 100 years, and few people doubt it.
However, lavoisier was never prepared to accept the predecessors' theories intact, and phlogiston theory was no exception. He is going to illustrate the problem with experiments. Starting from 1772, he began to study the combustion problem and conducted a series of experiments.
1774, British chemist priestley prepared oxygen by heating mercury oxide, and conducted experiments on the characteristics of oxygen with mice and plants. However, he failed to get rid of the shackles of "phlogiston theory" and thought it was a kind of "phlogiston-free gas". On August 30th this year, lavoisier received a letter from Swedish chemist Scheler. In the letter, Scheler suggested that he do an experiment and get a kind of "flame air" (actually oxygen), but lavoisier didn't pay enough attention to this letter. On June+10, 5438, priestley visited Paris, met lavoisier, and introduced his experiment of discovering "phlogiston gas" to lavoisier. Lavoisier thought of Scheler's "flame air" again, and then he began to pay attention to this kind of experiment.
From June 1774 to March 1775, lavoisier repeated the experiment of priestley and Scheler. After careful research and thinking, he scientifically summarized the research results of Boyle, Scheler and priestley. Then in 1778, he called "flame air" the pure part and breathable part of air, and later named it "oxygen". This view has greatly broken through the ideological shackles of "phlogiston theory" and made a historic breakthrough.
1783, he published a book "general theory of combustion" and systematically put forward the "oxidation theory". To this end, he organized a family dance to commemorate this historic event. At the beginning of the dance, lavoisier held high his newly published General Theory of Combustion and solemnly declared that "water is the product of oxygen and hydrogenation" in front of many guests. His wife publicly burned the works of Starr, a German chemist and physician of the King of Prussia, about phlogiston, symbolically announcing the end of the phlogiston era and the arrival of a new chemical era.
Lavoisier's chemical theory, like a revolutionary storm, destroyed the phlogiston theory. However, in the eighth year after the publication of The General Theory of Burning, he himself was blown down politically by the revolutionary storm.
179165438+1On October 27th, Mara, an outstanding representative of the French bourgeois revolutionary democrats, publicly named and attacked lavoisier in his "Friends of the People". This is mainly because lavoisier has a close relationship with the French Louis Dynasty, and some remarks are inevitably influenced by the royal family. Mara enjoys high prestige among the broad masses of the people, and his abusive attack is tantamount to a death sentence. Soon, the revolutionary regime ordered the arrest of lavoisier.
1794 in may, the court tried lavoisier in public. Lavoisier's defense lawyer asked the judge to consider lavoisier's special contribution to science in his defense, hoping to be lenient. However, Crowe Hall, the vice president of the court, said: "The Republic does not need scientists!"
Lavoisier said in the final statement of the court: "I am willing to be deprived of everything by the revolutionary regime, as long as I am allowed to be an ordinary pharmacist and do some chemical experiments." But Judge Mylan said, "There are too many French scholars! You can't live through death. "
"Since the court is going to sentence me to death, I make one last request, asking the court to suspend the execution of the death penalty for two weeks. Before I went to prison, I was doing an important experiment about sweat secretion. Let me finish this experiment before I die. " Lavoisier pleaded with the judge for the last time.
"Now is the revolutionary period. What effect does your sweat secretion experiment have on the revolution? " The judge asked sarcastically.
In this way,1on may 8, 794, lavoisier was pushed to the guillotine.
After lavoisier's death, the French mathematician said, "It only takes a moment to cut off lavoisier's head, but it may take France a century to recreate such a head!"