International Year of Chemistry 2011 – Commemorating Marie Curie

Preface

The year 2011 has coincided with the 100th anniversary of the Nobel Prize for Chemistry awarded to Marie Sklodowska-Curie (1867-1934), one of the most extraordinary persons in all of human history.  It also marks the 100th anniversary of the founding of the International Association of Chemical Societies. To commemorate these events as much as to highlight chemistry as a creative science essential for sustainability and improvements to our way of life under the unifying theme “Chemistry—our life, our future”,  UNESCO and the International Union of Pure and Applied Chemistry (IUPAC) have both actively promoted celebration of this year worldwide as the International Year of Chemistry (IYC).  As additional rationale for doing so, the organizing committee of IYC points out that; "All known matter – gas, liquid and solid – is composed of the chemical elements or of compounds made from those elements.  Humankind’s understanding of the material nature of our world is grounded in our knowledge of chemistry.  Indeed all living processes are controlled by chemical reactions".

IYC 2011 parallels the International Year of Physics 2005 commemorating the centenary of the historic contributions of Albert Einstein that revolutionized our understanding of the laws of Nature and the International Year of Astronomy 2009 marking the 400th anniversary of Galileo's sensational discoveries about the universe around us with the first ever astronomical telescope.

Beginning with a two-day inaugural ceremony at the UNESCO headquarters in Paris on Jan 27-28 featuring several eminent scientists and personalities from around the world, the IYC activities spanned out all over the world with the objectives of

•  Increasing public appreciation of Chemistry in meeting world needs.
• Encouraging an interest in Chemistry among young people.
• Generating enthusiasm for the creative future of Chemistry.
• Celebrating the achievements of Marie Curie and the contributions of women to Chemistry.

Supported by a multimedia presentation, I have had several opportunities to talk to students and teachers about the life and work of Marie Curie, encompassing her contributions to both Chemistry and Physics, as part of IYC 2011.  This brief assessment of the life and work of Marie Curie is essentially based on it and represents my own tributes to this great personality.

The Curies' place in History

Marie Curie is undoubtedly the greatest woman scientist of all time and one of the greatest women in human history.  She not only won Nobel prizes in both Chemistry and Physics, but was also the only person ever to win two Nobel Prizes in two separate science disciplines (Chemistry in 1911 and Physics earlier in 1903) in the long history of Nobel awards dating back to the beginning of the twentieth century.  Considering the voluntary and selfless work she had done during the First World War using radioactive radiations and X-rays to alleviate the sufferings of soldiers and people at large, she could have been justifiably awarded the Nobel Peace Prize also.

Incidentally, John Bardeen of USA and Frederick Sanger of Britain were the only persons to win two Nobel awards in the same science discipline – Bardeen for Physics (in 1956 and 1972) and Sanger for Chemistry (in 1958 and 1980).  Apart from these three, Linus Pauling of USA was the only individual to win two Nobel prizes – for Chemistry and Peace in 1954 and 1962, respectively.  [In my view, someone like Albert Einstein deserved at least three Nobel prizes in Physics alone, but was given only one, that too not for his greatest contributions to science in the form of the theories of relativity.]

Though born and brought up in occupied Poland, Marie Curie was the central figure of the Curie family of France which together accounted for an astonishing five Nobel prizes among its four key members including husband Pierre Curie, daughter Irene Joliot Curie and Irene's husband Frederic Joliot Curie who honored the Curie family as much as the world of science by formally appending the Curie name to his own surname. In 1903, Marie and Pierre had been awarded a joint share of the Nobel Prize for Physics along with Henri Becquerel for the discovery and subsequent work on natural Radioactivity.  By a strange coincidence, the Nobel Prize for Chemistry in 1935 was jointly awarded to Irene and Frederic for their discovery of artificial Radioactivity, achieved through the synthesis of new radioactive elements.  In 1911 the Nobel Prize in Chemistry was awarded exclusively to Marie Curie "in recognition of her services to the advancement of chemistry by the discovery of the elements radium and polonium, by the isolation of radium and the study of the nature and compounds of this remarkable element".

Early Life

Born in Warsaw, Poland to parents who were both teachers, Maria Sklodowska was the youngest and brightest of five children, with a strong intellectual disposition permeating the whole family.  They were staunchly nationalistic in outlook in a country that was under Russian occupation at that time and resented every bit of it.  Much of Maria's early education took place in the informal atmosphere of a 'floating university' about which she later wrote; "It was one of those groups of Polish youths who believed that the hope of their country lay in a great effort to develop the intellectual and moral strength of the nation....we agreed among ourselves to give evening courses, each one teaching what he knew best".  Her interest in Science had been strongly influenced by her father and she later said; "During these years of isolated work, trying little by little to find my real preferences, I finally turned towards Mathematics and Physics, and resolutely undertook a serious preparation for future work".

 

The early loss of her mother was compounded by a difficult financial situation in the family that threatened to interfere with the children's education. To promote her sister Bronya's medical education, Maria took up employment as a governess to a rich family for two years and then received reciprocal support from Bronya when she moved to Paris in 1891 to further her own education in the famous Sorbonne University.   The lost time meant that she had to do a lot of catching up with Mathematics and Science apart from having to learn a new language.  She stood up to the challenge so well that she topped in her Physics studies and earned a much needed scholarship that secured her academic future.

Life and Work in Paris

Her scholarship meant that Maria could live close to her university campus and spend long hours on her studies and work.  She came under the tutelage of the renowned physicist Gabriel Lippmann and became intimately acquainted with another promising physicist of the day, Pierre Curie.  About Pierre, she later remarked; "I noticed the grave and gentle expression of his face, as well as a certain abandon in his attitude, suggesting the dreamer absorbed in his reflections.”  The mutual respect and admiration between the two grew rapidly, culminating in their marriage in 1895; Maria Sklodowska became Marie Curie. Exploring the countryside by bicycle was one of their memorable pastimes in those days.

In 1896 Henri Becquerel discovered Radioactivity, a termed coined later by Marie, with a uranium compound and the Curies got interested in studying this phenomenon extensively.  Facilities for experimental research work in those days were poor and the Curies had to endure very difficult conditions. They also had to do a considerable amount of teaching as part of their duties. Pierre was yet to complete his doctoral work and it was with Marie's strong support and encouragement that he did so even as she struggled with her own household and professional responsibilities. Their daughter Irene was born in 1897, further augmenting her work load.  Commenting on this period of her momentous life, Marie said; “It became a serious problem how to take care of our little Irene and of our home without giving up my scientific work. Such a renunciation would have been very painful to me, and my husband would not even think of it... the close union of our family enabled me to meet my obligations.”

Marie made the puzzling discovery that the level of radioactivity in the uranium compound used by Becquerel was considerably less that in pitchblende, the naturally occurring ore from which uranium is obtained.  She reasoned that the ore contained minute quantities of other element/s more strongly radioactive than uranium itself. Deciding to put her hypothesis to test, she started extensive investigations with the aim of separating such elements from pitchblende and testing for their radioactivity.  This is when Marie Curie transformed herself into a celebrated chemist, adding to the considerable prowess she had already achieved in physics, eventually winning the Nobel Prize for both.  Pierre was so intrigued by Marie's work that he joined forces with her.  In her investigations, Marie benefitted enormously from a sensitive device called the piezoelectric electrometer invented earlier by Pierre and his brother Jacques.  This was used to detect and measure accurately small electric currents produced by the ionization of air when impacted by the energetic radioactive radiations. She also managed to get a tonne of pitchblende ore as a gift from the Austrian government as raw material for their experiments.

Nobel Prize for Physics

In 1903 the Nobel awards committee had initially considered Henri Becquerel and Pierre Curie for the Physics prize, ignoring Marie.  It may have perceived the role of Marie as only that of a familial assistant.  When Pierre came to know about this, he let it be known that Marie's contribution had been even greater than his own and the award would not be acceptable to him without her inclusion.  The committee acquiesced and announced the prize to all three of them. One wonders how much of male chauvinism was involved in this episode.  Some of it was certainly evident when the Royal Institution of London invited Pierre to deliver a special lecture on the topic the same year, apparently ignoring Marie. It is not out of place to point out that those were still the days of Woman Suffrage movements, even in the civilized world! Incidentally, Marie was the first woman to break into the ranks of Nobel laureates.

Sadly, both were too ill to travel to Stockholm and receive the Nobel Prize that year, but the Curies together did so in a special ceremony in June 1905 and Pierre delivered the traditional Nobel Lecture.

 

The Curies' second daughter, Eve, was born in 1904 even as they continued with their greatest investigation that eventually led to the discovery of two new radioactive elements, Polonium and Radium.  Unlike her mother and sister, Eve took to music and arts and became Marie's biographer.

Polonium and Radium

It was a herculean task to track down the suspected radioactive elements in pitchblende, a highly complex mineral made up of a large number of different elements. To isolate the unknown elements present only in extremely small amounts, the Curies had to come up with radically new methods of chemical analysis and separation.  They managed to secure an abandoned shed to set up their facilities from scratch and had to carry out their work in extraordinarily primitive conditions, exposed to the vagaries of nature all the time.  Reminiscing on these times Marie later remarked; "There was no question of obtaining the needed proper apparatus in common use by chemists....Sometimes I had to spend a whole day mixing a boiling mass with a heavy iron rod nearly as large as myself. I would be broken with fatigue at the day's end".  The grinding hard work had also its compensations as when she said; "One of our pleasures was to enter our workshop at night; then, all around us, we would see the luminous silhouettes of the beakers and capsules that contained our products".

   

The Curies identified two strongly radioactive fractions in pitchblende, one containing mostly bismuth and the other mostly barium.  Focusing their initial efforts on the fraction containing bismuth, they determined that it contained a new element with properties very similar to bismuth, but radioactive. They named it Polonium, in honor of Poland, Marie's country of birth, for which she had retained a strong emotional attachment.  Their later efforts with the second fraction unraveled the existence of another, vastly more radioactive, element which was given the name Radium.

To complete their work, the Curies had to actually isolate Radium in its elemental form from the ore and establish its properties, including the strength of its radioactivity.  This was even more challenging and taxing than their earlier work and required a supreme effort of scientific faith, persistence and perseverance, unparalleled in the annals of science. There are few instances in the history of human endeavour where so much has been accomplished by so few in so short a time, with so little external support and in such appalling working conditions.

To separate the radium from the barium, Marie used a method of fractional crystallization of the chloride. The radium salt, less soluble than the barium salt, became concentrated in the crystals. Fractionation is a lengthy, hugely laborious and methodical operation which gradually eliminates the barium and enriches the radium content. To obtain a very pure salt she had to perform several thousands of successive crystallizations. The progress of the fractionation was monitored by activity measurements at each stage.

The climax was the isolation of just 0.1 gram of radium chloride from as much as one ton of pitchblende. A microscopic quantity of pure radium was eventually extracted from this by Marie Curie and her former assistant Andre Debierne in 1910.

  

Much of the early work was reported in Marie Curie's highly acclaimed doctoral thesis in Physics in 1898.

Tragedy and Adjustment

Marie's life was shattered by the tragic death of husband Pierre in a road accident in April 1906. As someone put it, "Pierre was not careful enough when he was walking in the street, or when he rode his bicycle; he was thinking of other things". Now Marie had to recover from the shock and sorrow by thinking of other things as evident from her remark, "Crushed by the blow, I did not feel able to face the future. I could not forget, however, what my husband used to say, that even deprived of him, I ought to continue my work.”  She quickly immersed herself in more work, declined a pension she was entitled to and instead, gratefully stepped into the professorship at Sorbonne that became vacant on Pierre's death and graciously offered to her.  She resumed teaching exactly where Pierre had left off, determined to maintain the continuity.

 

By now Marie had become famous both within and outside the country and state-of-the-art laboratory facilities were provided liberally to her and her team, a far cry from the days of working in an abandoned shed from where, ironically, her greatest contributions to science had been made.  The history of science is replete with such instances where monumental work has been accomplished with the most primitive of facilities and tools.  Buoyed by the support and attention she was receiving, Marie began to dream of a 'Radium Institute' as a world centre for the study of radioactivity.  This became a reality later, both in her adopted country and the country of her birth.

1911 and Nobel Prize for Chemistry

The year 1911 was as tumultuous as it was momentous in the life of Marie Curie.  The Curies (all four of them) held strongly leftist views and didn't endear themselves to the extreme right wing intellectuals and their supporters in France. Marie's attempt to get elected to the prestigious French Academy of Sciences was defeated by their machinations. If elected, it would have been a greater honor to the Academy itself than to Marie. Worse still, she was accused of improper conduct in what came to be known as the Langevin Affair, involving the brilliant French physicist Paul Langevin, a former protégé of Pierre Curie and admirer of Marie. A ruckus was created around it; right wing newspapers blew it out of proportion and launched an ugly attack on Marie, even forcing her to flee to England for some time to escape the mental torture inflicted on her.

 

The announcement of the Nobel Prize in Chemistry exclusively to Marie that year soon followed in spite of her troubles and their public perception. Apparently, Marie's monumental work on the discovery and isolation of Radium and its rapidly increasing medical and industrial applications could no longer be ignored.  In effect the Nobel organization undid the damage done earlier to her reputation by the French Academy and the right wing intellectuals.

 

In her Nobel acceptance lecture, Marie paid homage and rich tributes to the memory of Pierre as well as to Rutherford whose work in England had laid the foundation for the understanding of radioactivity as fundamentally an atomic phenomenon.  Of course it later came to be associated with the physical changes taking place inside the atomic nucleus and became part of nuclear physics.  Referring to her own work, Marie observed; "It can be said that the task of isolating radium is the corner-stone of the edifice of the science of radioactivity. Moreover, radium remains the most useful and powerful tool in radioactivity laboratories. I believe that it is because of these considerations that the Swedish Academy of Sciences has done me the very great honour of awarding me this year's Nobel Prize for Chemistry."

Also in 1911, Marie Curie was the only woman at the prestigious Solvay Conference, a gathering of the world's top physicists and chemists, promoted by the Belgian industrialist Ernest Solvay.  Discussions at this gathering opened the way to major advances in physical science that would bring together Relativity, Quantum Physics/Chemistry and Nuclear Physics/Chemistry which were all still in their infancy.  Marie Curie's work on radioactivity was also very much in focus.  The following is a photograph taken at this conference, showing a gathering of some of the greatest scientific minds of the time.  An unmistakable Marie Curie is seen to be conferring with Henri Poincare.   Standing second from right is Albert Einstein, with Paul Langevin to his left.  Standing tall just behind Marie is Ernest Rutherford. Max Planck is seen standing second from left.

Marie's Foresight and Vision

The following entry on Radium in the 13th edition (1926) of the Encyclopedia Britannica is highly significant and indicative of Marie's foresight and vision even during the early days of radiology:

"One of Marie Curie’s outstanding achievements was to have understood the need to accumulate intense radioactive sources, not only to treat illness but also to maintain an abundant supply for research in nuclear physics; the resultant stockpile was an unrivaled instrument until the appearance after 1930 of particle accelerators. The existence in Paris at the Radium Institute of a stock of 1.5 grams of radium in which, over a period of several years, radium D and polonium had accumulated made a decisive contribution to the success of the experiments undertaken in the years around 1930 and in particular of those performed by Irene Curie in conjunction with Frederic Joliot, whom she had married in 1926. This work prepared the way for the discovery of the neutron by Sir James Chadwick and, above all, for the discovery in 1934 by Irene and Frederic Joliot-Curie of artificial radioactivity."

Later Life and Celebrity Status

Germany's declaration of war on France in 1914 and the ensuing First World War forced major changes in the life and work of Marie Curie.  As a precaution the entire stockpile (about one gram) of Radium was moved out of Paris to an undisclosed location.  She was actively involved in the setting up of military radiology centres in aid of soldiers.  With daughter Irene she contributed substantially to hospital services.  They trained women in X-ray technology for War related applications and supervised deployment of mobile X-ray vans in war zones.  They also trained American soldiers in radiological work.

After the First World War she embarked on a vigorous 'radium campaign' that attracted worldwide attention and received funding from the French philanthropist Henri de Rothschild.  Admires in America led by noted journalist Mrs William Meloney raised a huge donation of one gram of Radium.  She received more aid for her campaigns during a visit to the USA in 1921 when she also met President Harding.  Academic honours and honorary degrees followed her everywhere.  She became an international celebrity, a status she was never really comfortable with any more than Einstein who acquired a similar status later. Significantly, Einstein himself made the remark; "Marie Curie is, of all celebrated beings, the one whom fame has not corrupted."  She paid a second visit to the USA in 1929 during which she met President Hoover.  This time she raised enough resources for the Warsaw Radium Institute founded earlier in 1925 with her sister Bronya as director.

Reflecting on her mother's celebrity status, her daughter and biographer Eve Curie wrote later; "My mother was 37 years old when I was born. When I was big enough to know her, she was already an aging woman who had reached the summit of renown. And yet it is the 'celebrated scientist' who is strangest to me - probably because the idea that she was a 'celebrated scientist' did not occupy the mind of Marie Curie. It seems to me rather, that I have always lived near the poor student, haunted by dreams, who was Marie Sklodowska long before I came into the world."

The End

Today the deadly effects of large doses of radioactive radiations on human physiology are very well understood, but almost totally unknown during the days of the Curies who used to work with them for long hours with almost no protection of any kind.  Unknowingly, they were exposing themselves to such intense levels of radiation and for such long periods of time that they are considered absolutely disastrous today.  Only when Marie showed unmistakable signs of burning on her fingers and hands in the early days were any suspicions raised about the deleterious effects of the radiations she had so painstakingly discovered.  Ironically, what she was so assiduously promoting as a diagnostic and curative measure for many of human afflictions was itself to spell her doom. She died of leukemia in July 1934, obviously contracted from her long exposure to radioactive radiations, as great a martyr to the cause of one's profession as anyone in history.  Considering the odds stacked against her, it is rather remarkable that she lived as long as she did.

Tributes

 

The year 1998 marked the centenary of the discovery of Polonium and Radium.  Poland, Marie Sklodowska's motherland, which had only recently become a truly free and independent country in its long history of oppression by foreign occupation and influence, decided to honour her memory by holding an international conference attended by over a hundred scientists from thirteen countries, including twelve Nobel laureates, to discuss 'prospects of contemporary physics and natural sciences, global ecological threats and the responsibility of scientists for the results of their research'.  As the International Year of Chemistry 2011 approaches its end just a few days from now, the worldwide tributes being renewed to her memory couldn't be better deserved.

  

Tailpiece

As I was about to upload this post, I remembered having seen a Hollywood movie titled Madame Curie long ago in my student days and wanted to see it again for whatever it was worth.  This 1943 MGM movie starring Greer Garson as Marie, Walter Pidgeon as Pierre and directed by Mervyn LeRoy, has some short but very appropriate background narration by the famous Aldous Huxley.  Though it had not won any of the many Academy Awards for which it had been nominated, it was nevertheless well worth seeing despite the extensively fictionalized and contrived scenes and story line that most such movies are guilty of.  Greer Garson was far too beautiful to portray Marie, but filled the role creditably otherwise. Walter Pidgeon was tailor-made for Pierre.  The laboratory scenes showing the trials, tribulations, agony and ecstasy of the Curies are very impressively portrayed.

While I do recommend this two-hour long movie to most readers, science students will find the 10-minute award winning documentary simply titled Marie Curie, produced by a young American student, particularly educative and informative.  I have used it as part of my multimedia presentations on Marie Curie.  It can be viewed at:

http://www.youtube.com/watch?v=0vTRrZU-LKQ