March 7,1999 Chemistry Report Period 6 Marie and Pierre Curie And the Discovery of Polonium and Radium Marie Marie Sklodowska ( a. k. a. ) was born in Warsaw in 1867. Her parents were teachers who believed strongly in the importance of education. Marie had her first lessons in physics and chemistry from her father. She had a brilliant aptitude for study and a great thirst for knowledge; however, advanced study was not possible for women in Poland. Marie dreamed of being able to study at the Sorbonne in Paris, but this was beyond the means of her family.
To solve the problem, Marie and her elder sister, Bronya, came to an arrangement: Marie should go to work as a governess and help her sister with the money she managed to save so that Bronya could study medicine at the Sorbonne. When Bronya had taken her degree she, in her turn, would contribute to the cost of Marie’s studies. So it was not until she was 24 that Marie came to Paris to study mathematics and physics. Bronya was now married to a doctor of Polish origin, and it was at Bronya’s urgent invitation to come and live with them that Marie took the step of leaving for Paris.
By then she had been away from her studies for six years, nor had she had any training in understanding French. But her keen interest in studying and her joy at being at the Sorbonne with all its opportunities helped her surmount all difficulties. To save herself a two-hour journey, she rented a little attic in the Quartier Latin. There the cold was so intense that at night she had to pile on everything she had in the way of clothing so as to be able to sleep.
But as compensation for all her privations she had total freedom to be able to devote herself completely to her studies. After two years, in 1893, she took her degree in physics, and in the following year, in 1894, she came second in a degree in mathematics. After three years she had brilliantly passed examinations in physics and mathematics. Her goal was to take a teacher’s diploma and then to return to Poland. There occurred an event that was to be of decisive importance in her life. She met Pierre Curie.
He was 35 years old, eight years older, and an internationally known physicist, but an outsider in the French scientific community a serious idealist and dreamer whose greatest wish was to be able to devote his life to scientific work. He was completely indifferent to outward distinctions and a career. He earned a living as the head of a laboratory at the School of Industrial Physics and Chemistry where engineers were trained and he lived for his research into crystals and into the magnetic properties of bodies at different temperatures. His father, who was a physician, educated him with the help of a private teacher.
Pierre with help from his brother discovered piezoelectricity, which means that a difference in electrical potential is seen when mechanical stresses are applied on certain crystals, including quartz. Such crystals are now used in microphones, electronic apparatus and clocks. Marie and Pierre discovered that they had a fondness for each other. They married at the town hall at Sceaux, where Pierre’s parents lived. They were given money as a wedding present, the invested it for some bikes. The two mostly study and often took bike rides to relax.
With persuasion by Marie and Pierre’s father, Pierre submitted his doctoral thesis in 1895. It concerned “different types of magnetism, and contained a presentation of the connection between temperature and magnetism that is now known as Curie’s Law”. In 1896 Marie passed her teacher’s diploma, coming first in her group. Pierre and Marie had a daughter Irene who was born in September 1987. Pierre had managed to arrange that Marie should be allowed to work in the school’s laboratory, and in 1897 she finished a number of investigations into the magnetic properties of steel on behalf of an industrial association.
Deciding after a time to go on doing research, Marie looked around for a subject for a doctoral thesis. Marie decided to make a systematic investigation of the mysteries “uranium rays, after fellow colleague Becquerel’s discovered that gases through which the rays pass become able to conduct electricity. She had an excellent help at her disposal an electrometer for the measurement of weak electrical currents, which was constructed by Pierre and his brother, and was based on the piezoelectric effect. Just after a few days Marie discovered that thorium gives off the same rays as uranium.
Her lasting systematic studies of the different chemical compounds gave the surprising result that the strength of the radiation did not depend on the compound that was being studied. It depended only on the amount of uranium or thorium. Chemical compounds of the same element generally had very different chemical and physical properties: one uranium compound is a dark powder, the another is a transparent yellow crystal. But Marie wondered what was affective for the radiation they gave off. What was only the amount of uranium they contained.
The she drew the conclusion that the ability to radiate did not depend on the order of the atoms in a molecule, it must be linked to the interior of the atom itself. This discovery was absolutely revolutionary. From a conceptual point of view it is her most important contribution to the development of physics. She now went through the whole periodic system. Her findings were that only uranium and thorium gave off this radiation. Marie’s next idea, simple but brilliant, was to study the natural ores pitchblende contain uranium and thorium.
She got samples from geological museums and found that the ores were four to five times more active than the amount of uranium. It was her guess that a new element was far more active and than uranium was present in small amounts in the ore. Interesting new ideas were opening up. Pierre gave up his research into crystals and symmetry in nature, which he was strongly, involved in and joined Marie in her project. They found that the strong activity came with the fractions containing bismuth or barium.
When Marie continued her analysis of the bismuth fractions, she found that every time she managed to take away an amount of bismuth, a residue with greater activity was left. At the end of June 1898, they had a substance that was about 300 times more strongly active than uranium. In the work they published in July 1898, they write, ‘ We thus believe that the substance that we have extracted from pitchblende contains a metal never known before, akin to bismuth in its analytic properties. If the existence of this new metal is confirmed, we suggest that it should be called polonium after the name of the country of origin of one of us’.
It was also in this work that they used the term radioactivity for the first time. After another few months of work, the Curies informed the l’Acadmie des Sciences, on 26 December 1898, that they had demonstrated a reason for having come upon an additional very active substance that behaved chemically almost like pure barium. They suggested the name of radium for the new element. In order to prove the new elements, the Curies would have to produce them in reliable amounts, they would have to determine their atomic weight and preferably isolate them.
To do this the Curies would need tons of the costly pitchblende. Marie considered that radium ought to be left in the residue. A sample was sent to them from Bohemia and the slag was found to be even more active than the original mineral. Several tons of pitchblende was later put at their disposal through the good offices of the Austrian Academy of Sciences. It was now that there began the heroic poque in their life that has become legendary. The two needed more room for their research, the principle at the school Pierre used to work at helped him. He let them use a large shed, which was not being used.
They’re the work of separation and analysis began. Marie performed the chemical separations, while Pierre did the measurements after each successive step. Physically it was heavy work for Marie. She processed 20 kilos of raw material at a time. She had to clear away pine needles and debris, then she had to undertake the work of separation. In that shed they performed their experience and Marie writes that they spent the best times of their lives. Sometimes they could not do their processing outdoors, so the harmful gases had to be let out through the open windows.
The only furniture was an old, worn pine table where Marie worked with her costly radium fractions. Since they did not have any shelter in which to store their precious products the latter were arranged on tables and boards. The dangerous gases contained, among other things, radon – the radioactive gas which is a matter of concern to us today since small amounts are emitted from certain kinds of building materials. Marie finally from several tons of the original material – isolated one decigram of almost pure radium chloride and had determined radium’s atomic weight as 225.
She presented the findings of this work in her doctoral thesis on 25 June 1903. Later the two were to receive the Nobel Prize a few years later: Marie’s former teacher that they showed their work to expressed the opinion that the findings represented the greatest scientific contribution ever made in a doctoral thesis. Pierre had been invited to the Royal Institution in London where Pierre gave a lecture. Before the crowded auditorium he showed how radium rapidly affected photographic plates wrapped in paper, how the substance gave off heat in the semi-darkness he demonstrated the spectacular light effect.
He described the results that he got after trying them out on himself. He had wrapped a sample of radium salts in a thin rubber covering and bound it to his arm for ten hours, then had studied the wound, which resembled a burn, day by day. After 52 days a permanent gray scar remained. Pierre mentioned that this observation maybe a treatment for cancer. Fifty years afterwards the presence of radioactivity was discovered on the premises and certain surfaces had to be cleaned. Pierre was ill. His legs shook and sometimes he found it hard to stand upright.
He was in much pain. He consulted a doctor who diagnosed neurasthenia and prescribed strychnine. And the skin on Marie’s fingers was cracked and scarred. Both of them constantly suffered from fatigue. Evidently they had no idea that the radiation could have a harmful effect on their general state of health. Nobel Prize In 1903 Marie and Pierre Curie were awarded half the Nobel Prize in Physics. The citation was, in recognition of the extraordinary services they have completed by their researches on the radiation phenomena discovered by Professor Henri Becquerel’.
Henri Becquerel was awarded the other half for his discovery of spontaneous radioactivity. The health of both Marie and Pierre Curie gave rise to concern. Their friends tried to make them work less. Their dearest wish was to have a new laboratory but no such laboratory was in prospect. They never got a new laboratory they always worked in empty room at schools. On 19 April 1906 Pierre Curie was run over by a horse-drawn wagon near the Pont Neuf in Paris and was killed. Now Marie was left alone with two daughters, Irene aged 9 and Eve aged 2.
She was in shock. When she was offered support, she refused it. She then became the first woman ever appointed to teach at the Sorbonne. After some months, in November 1906, she gave her first lecture. The large amphitheater was packed. As well as students, her audience included people from far and near, journalists and photographers were in attendance. Many people had expected something unusual to occur. Perhaps some demonstration of the historic occasion. When Marie entered, thin, pale and tense, she was met by an ovation.
However the expectations of something other than a clear and factual lecture on physics were not fulfilled. But Marie’s personality, her aura of simplicity and competence made a great impression. Irene was now 9 years old. Marie had definite ideas about the upbringing and education of children that she now wanted to put into practice. Marie organized a private school with the parents themselves acting as teachers. Professors accordingly taught a group of some ten children. The little group became a kind of school for the elite with a great emphasis on science.
In 1908 Marie, as the first woman ever, was appointed to become a professor at the Sorbonne. Marie had opened up a completely new field of research: radioactivity. Various aspects of it were being studied all over the world In 1914, Marie was in the process of beginning to lead one of the departments in the Radium Institute established jointly by the University of Paris and the Pasteur Institute, After the Peace Treaty in 1918, her Radium Institute, which had been completed in 1914, could now be opened.
It became France’s most internationally celebrated research institute in the inter-war years.. She had to devote a lot of time to fund-raising for her Institute because she could not afford the uranium. She also became deeply involved when she had become a member of the Commission for Intellectual Cooperation of the League of Nations and served as its vice-president for a time. There she met Missy Wiskell In the last ten years of her life Marie had the joy of seeing her daughter Irne and her son-in-law Frederic Joliet do successful research in the laboratory.
She lived to see their discovery of artificial radioactivity, but not to hear that they had been awarded the Nobel Prize in Chemistry for it in 1935. Marie Curie died of leukemia on 4 July 1934. Pierre and Marie Curie’s work is greatly respected in Physics and in Chemistry. Bibliography Bensuade-Vincent, Bernadette, Marie Curie, femme de science et de lgende, Reveu du Palais de la dcouverte, Vol. 16. n 157 avril 1988, 15-30. Crawford, Elisabeth, The Beginnings of the Nobel Institution, The Science Prizes 1901-1915, Cambridge University Press, Cambridge, & Edition de la Maison des Sciences, Paris, 1984.
Curie, Eve, Madame Curie, Gallimard, Paris, 1938. In English, Doubleday, New York. Curie, Marie, Pierre Curie and Autobiographical Notes, The Macmillan Company, New York, 1923. Subsequently Marie Curie refused to authorise publication of her Autobiographical Notes in any other country. Gleditsch, Ellen, Marie Sklodowska Curie (in Norwegian), Nordisk Tidskrift, rg. 35, 1959. Kandinsky, Wassily, Look Into the Past 1901-1913, The Blue Rider, Paul Klee. Franz Marc, New York 1945.
Langevin, Andr, Paul Langevin, mon pre, Les diteur Franais Runis, Paris, 1971. Marbo, Camille (Pseudonym for Marguerite Borel), Souvenirs et Rencontres, Grasset, Paris, 1968. McGrayne, Sharon Bertsch, Nobel Prize Women in Science, Their Lives, Struggles and Momentous Discoveries, A Birch Lane Press Book, Carol Publishing Group. Nobel Lectures including Presentation Speeches and Laureates’ Biographies, PHYSICS 1901-21. Published for the Nobel Foundation in 1967 by Elsevier Publishing Company, Amsterdam-London-New York.
Nobel Lectures including Presentation Speeches and Laureates’ Biographies, CHEMISTRY 1901-21. Published for the Nobel Foundation in 1967 by Elsevier Publishing Company, Amsterdam-London-New York. Pflaum, Rosalynd, Grand Obsession: Madame Curie and Her World, Doubleday, New York, 1989. Quinn, Susan, Marie Curie: A Life, Simon & Schuster, New York, 1995. Ramstedt, Eva, Marie Sklodowska Curie, Kosmos. Papers on Physics (in Swedish) published by Svenska Fysikersamfundet, nr 12, 1934. Reid, Robert, Marie Curie, William Collins Sons & Co Ltd, London, 1974.