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Uery Discovered Deuterium ¨C A Comedy of Errors

2007-9-25

Have you seen The Comedy of Errors, one of Shakespeare's comedies, a playwright making people can't help laughing? There were two pairs of twins in the play, so identical in appearance that their wives couldn't make sure which was which. As a result, numerous silly jokes took place in life that plunged them in troubles. As the elder brother said, "We both had mistaken our wives so that so many errors were made." ¡¡¡¡
Interesting enough, some "comedies of errors" often occur in scientific studies. Some scientists would disclose some great discoveries according to certain seemingly wrong ideas and eventually won the Nobel Prize. Here we take an example of American scientist Uery, who won The Nobel Prize in Chemistry 1934 because of a mistaken conclusion.
Penniless Pocket, Strong Mind
On April 29, 1893, Uery was born in a priest family in Walkerton IN USA; at six, his father died and his mother remarried and moved with his stepfather to a ranch in MT Canada.
As the ranch situated in a pretty desolate and backward area, no people with higher education would like to come and each school was in high demand for teachers. Uery recalled during his middle school there was not a single teacher staying over one year. They mostly were in the mood of transferring to a better place after a half year or longer teaching in this place.
In 1911, Uery finished his high school at 18 only, when he was longing and dreaming for entering college. His teacher also told him, "Uery, you're a smart boy and should go to college for further studies. You can create yourself a better future.". "Thank you, Sir, but¡­".
But what? Because his stepfather's ranch wasn't making profits and the poor economic standing of the family could hardly afford his college expenses. It happened that Montana State University was in demand of teachers, and because of his outstanding academic work his teacher recommended him to teach. Uery found it a good chance to earn money for college studies as well as strengthen his knowledge and learn more, and agreed.
Uery taught for three years, during which he was diligent and responsible, and good teaching effects were achieved. After that, the president tried to persuade him to continue his teaching. Uery's parents were very pleased at this, but Uery turned down his kindness and continued pursuing his dream for further studies.
In autumn of 1914, Uery finally was admitted to Zoology and Chemistry in Montana State University. As he had no enough money to afford the tuition, he figured out three ways to earn money. First he lived and studied in a tent set up on an open space to save money; second, he worked part-time in railway construction crew during vacations; third, he managed to obtain full credits and finish the 4-year course within three years. Finally Uery obtained the Bachelor Degree in 1917.
But the Bachelor Degree wasn't his ultimate goal, he was still considering to continue a postgraduate study. As the research institute had a few of assigned numbers for students, only a rarely small part of excellent talents could be admitted. It happened the World War I exploded, and Uery went to work as Chemical Analyst in Barrett Chemical Company, a company manufacturing military goods in Philadelphia to the east coast of America. After the war, Uery returned to Montana and taught Chemistry in Montana State University for two years.
In 1921 Uery was admitted to the postgraduate program of the Chemistry Dept. University of California, Berkeley. Then he continued the Doctorate study under the tutorship of famous chemist Lewis and in 1923 at 30 he obtained the Doctorate Degree he dreamed of.
Soon after graduation Uery was recommended to Denmark Bohr to engage in the study of nucleonics for one year. He now was an experienced Physicochemist when he was again back to America.
A Fascinating Riddle
At that time there was an unsettled fascinating riddle in the chemistry world. Uery was also ambitious in encoding the riddle through his study.
In order to clarify what the riddle is, I'd like to introduce a bit of chemistry knowledge. In chemistry there's a term called "isotopes", which means some atoms with same number of electrons rotating around the nucleus but different masses. The extranuclear electron numbers determines the chemistry property of the atom. So several isotopes, similar in chemistry property but different in mass, occupy the same position in the "Periodic Table of Elements", and the term "isotope" is hereby given.
For example, Neon (Ne) has two isotopes, one with mass of 20 (20Ne) and the other of 22 (22Ne). 20Ne and Ne both have ten electrons rotating around the nucleus, with similar chemistry properties but different masses. Different isotopes account for fixed proportion in a certain number of atoms. Taking an example, Oxygen (O) has a relative atomic mass of 16, having two isotopes with different relative masses of 17 and 18. They're separately labeled as 16O, 17O, 18O, with 18O accounting for 1/1250 of 16O, and less proportion for 17O.
Ne has two isotopes discovered in 1919, and O, three isotopes in 1929. Then what about Hydrogen (H), the lightest atom in world (with the relative atomic mass of 1)? This question aroused the chemists and physicists to explore the isotopes of H which could be applied to the study other atoms.
Some thought H had isotopes, and others not.
In 1919 German Physicist Otto Stem (Laureate of the Nobel Prize in Physics 1943) ever proposed an opinion, regarding such a small relative atomic mass 1.0079 of H was most likely the compound of two isotopes of H. He also predicted the relative atomic mass of one H atom was 1 (1H), the mass of the other H atom was 2 (2H) which merely accounted for 1% of H. Based on this conception, he tried to find 2H, but failed. He was disappointed and thus concluded that H atom had no isotopes.
But Uery's tutor Lewis persistently believed H must have isotopes. So did Uery.
Chart on the Lab Wall
How time flied and it came to 1930. Then the study on isotopes had become the hot topic and many scientists were vigorously engaging in the discovery of isotopes of various atoms. At the same time Nucleonics was developing.
Whether H had isotopes or not remained a riddle. Uery still believed H did have isotopes. Once Uery took a taxi with a famous professor Hillebrand on the way to a meeting, and he asked, "Prof. Hillebrand, what are you busy with?"
"I'm very interested in the research of Giauque and Johnston. What about you?"
"Ah. Did they discover the two isotopes of Oxygen, with one relative atomic mass of 17 and the other of 18?"
"Yes. They will publish the paper soon."
After short contemplation, Hillebrand continued to say, "They can't find any isotopes of other key elements?"
Uery couldn't agree to his opinion, and said "No, Hydrogen has no isotopes yet."
"Do you think Hydrogen have isotopes?"
"Definitely yes."
From this conversation, we can see that Uery had been confident in his tutor Lewis's judgment. But Uery wasn't blind in his belief and he had his own reason. On the lab wall, Uery hung a chart, on which the black disc represented the already known atomic nucleus and the circle for the unknown atomic nucleus. Uery linked the broken lines of the black disc and finally plotted a circle.
It was based on this broken line that Uery predicted the circle indicated that H had isotopes of 2H and 3H, and that Helium (He) had isotope 5He.
Some readers might help laughing, "Ah. How can a chart predict 2H and 3H never been known?"
In fact, great discoveries often are found without the confinement of conventions. Some are inspired by the heavy smog above the mountain, some are enlightened by a dream, and others suddenly see the light while in trip. The more you read such stories of scientists, the better you can perceive. Meanwhile, their stories also reveal that the interests, knowledge and open mind of a scientist are as important as diligence in great discoveries.
Discovery of Deuterium
Uery called 2H Deuterium (D), an isotope of H with one extranuclear electron, similar chemical property as H but different mass as twice as H. Although he believed in Deuterium, Uery didn't find it until 1931.
An incident in 1931 inspired Uery to determine to discover Deuterium. The story happened like this. In 1931 Physicist Birge and Astrophysicist Mentzer applied two methods to measure the relative atomic mass of H and found different values. Then Birge and Mentzer concluded H was definitely having isotope Deuterium, which accounted for 1/4500 of H.
Two days after he learned about this, Uery devised an optical experiment with an aim of finding Deuterium. Soon he proved the existence of Deuterium. In order to prevent possible errors, he cautiously adopted another method called "Fractionation" to find Deuterium. "Fractionation" is an approach to heat a liquid till steam which is again condensed to a liquid. For example, when heating the petroleum, various substances such as premium gasoline, regular gasoline, kerosene, etc. are abstracted from petroleum steam. Uery managed to separate H and D from the liquid hydrogen steam.
In the end, Uery achieved great success in discovering D by the fractionating process. D was supposed to account for 1/4000 of Hydrogen.
Both the optical method and the thermological method simultaneously proved the existence of D, so in 1931 Uery announced his finding.
Soon his discovery caught people's attention and was heated discussed. It seemed the puzzle Hydrogen isotopes was going to settled.
Objections from the Authority
The path to scientific discoveries is forever uneven and full of hardships. After Uery announced his discovery of D, British chemist Soddy immediately proposed his opposition, denying Uery's discovery of Hydrogen isotopes.
As Soddy won the Nobel Prize in Chemistry in 1921 for his discovery of isotopes, he was called "pioneer" of isotope research.
Why did Soddy oppose Uery? When discovering isotopes, Soddy defined Isotope as: the isotope of the same atom which couldn't be separated through chemical methods, the so-called "Chemical Inseparability". But Uery¡¯s discovery just contradicted with this definition, separating isotope H and D through heating and fractionation which was a chemical method. So Soddy said, "That Uery separated D from Hydrogen with the chemical method just indicates D is another type of Hydrogen atom instead of Hydrogen isotope, even though they are different in relative atomic mass!"
However Uery weren't blind in authority despite Soddy was the Nobel laureate in the chemical world. He was very confident in his discovery and noted that he was cautious and careful in his conclusion. He thought Soddy must be mistaken and determined to proclaim his findings in various science congress.
It sounds funny that Uery was lacking of traveling expenses to attend American Physics Society. But if Uery didn't clarify his ideas at the meeting, Soddy's opposition would endanger the recognition of D.
Luckily Uery was assisted by two generous executive officers and successfully presented his report at the meeting and responded to some concrete objections.
People came to understand and recognize Uery's discovery and perceive the significance of this discovery. Three years later, Uery was awarded the Nobel Prize in Chemistry. For Uery it was rare for a discovery to win the Nobel Prize in chemistry in such a short time.
Error in Error
As discussed beforehand, it was the prediction of Birge and Mentzer that urged Uery to discover D. Uery ever said, "Without Birge and Mentzer's prediction, there will be no D. Then it still takes a long time to discover D."
But unexpectedly when Uery was awarded the Nobel Prize in Chemistry for D discovery, British chemist Aston claimed in his article that there was error in Birge and Mentzer's measurement, so was their prediction of the existence of D.
Uery didn't observe the error in Birge and Mentzer's prediction while he was doing experiments until 1935. Although they were mistaken, Uery's discovery of D was true and his merit wouldn't be ignored. Interestingly enough, Uery discovered a great truth based on a wrong prediction, which urged him to find D with resolution.
When Uery addressed on the Nobel Prize awarding ceremony, he added a sentence to the already written speech, "After I finished my speech script, Aston, adopting a new measurement, proved Birge and Mentzer's prediction in 1931 wrong. I won't amend the speech, because their prediction was made before D discovery, so important that without which I couldn't find D".
Actually Uery was not the first one who found great discoveries from wrong prediction in science history. For instance, Becquerel, the laureate of Nobel Prize in Physiology 1903, discovered atomic radioactivity from three wrong predictions. What a wonder in the history of scientific discoveries!
They pioneered a new way in earth evolution and life origin. His postgraduate Miller and him did an interesting experiment, filling the mixture of ammonia, methane and hydrogen into a 5L flask in conjunction with a small 500ml flask with water. They would simulate the primitive conditions of the earth and study the existence of amino acid, the basic substance of life. Uery and Miller heated the water in the small flask till steam filled into the large flask with the mixture of the above three airs. They powered the electrode to start spark discharge, and froze the product generated to go back to the small flask. Keep discharge for a week and the product recycled constantly between the large and small flasks. One week later, they analyzed the ultimate product and found a number of amino acid, with glycin and alanine accounting for the majority.
This is the famous "Uery-Miller Experiment", which invented a new approach of experiment researching of life origin in earth. How marvelous!
In 1969 American astronauts mounted the moon and took back some rock samples, with which scientists would like to analyze if there was life on moon. They found it very hard to conduct such an analysis and to prevent wrong conclusions. But Uery said, "I can help."
He again made it in the end. As a 76-year-old man, he has been commended by his wisdom and ability.
When recollecting Uery's contribution in life, we can't help thinking of a saying of an ancient Greek sage, "To pursue truth is difficult on the one hand, but easy on the other hand, because the truth is neither completely grasped nor absolutely missed. So long as we accumulate a bit of nature knowledge, there will be huge."
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Organizer: Beijing Municipal Association for Science & Technology
Undertaker: Beijing Science & Technology Consulting Center,
Information Center of Beijing Municipal Association for Science & Technology