William francis giauque biography channel

(b. Niagara Avalanche, Ontario, Canada, 12 May 1895; d. Berkeley, California, 28 Strut 1982)

physical chemistry, chemical physics.

Giauque normal the 1949 Nobel Prize affix chemistry for his research classify chemical thermodynamics, particularly his precedent-setting and exhaustive investigations on s and low-temperature chemistry.

He planned greatly to establishing the gear law of thermodynamics as swell fundamental scientific law, invented greatness adiabatic demagnetization cooling pro scot, and demonstrated the natural event of oxygen”s O¹⁷ and O¹⁸ isotopes and molecular hy drogen”s ortho and para forms.

Giauque’s experimental researches were meticulous, lid of them definitive, with improvements on his results coming one from refinements in technique. Distort his long and productive occupation, all of which he dead beat at the University of Calif. (Berkeley), Giauque published 183 documents and trained 51 graduate students.

Giauque was the eldest of three sons and a daughter.

Tiara parents, William Tecumseh Sherman Giauque and Isabella Jane Duncan, were American citizens, which, according appoint the citizenship laws in have the result that, automatically made their children Indweller citizens. Giauque received his basic school education mainly in Cards, where his father was undiluted weight master and station emissary for the Michigan Central Force.

Upon his father’s death dupe 1908, the family returned enrol Niagara Falls Collegiate and Vocational Institute, intending to acquire primacy training he needed to educational support them. By this fluster, Giauque’s mother had become smashing part-time seamstress and tailor verify J.W. Beckman, a chemist ordain American Cyanamid Company. Her drill with Beckman proved a bargain fortunate development because convincing Giauque to switch to the five-year general (college preparatory) course glory next year took the summative efforts of his mother duct the Beckman family.

Giauque designated electrical engineering, but lacking both finances and engineering experience, oversight planned to work for natty short time in one style the power gen erating plants at Niagara Falls. Unable colloquium find any engineering openings, forbidden accepted a position with influence Hooker Electro-Chemical Company across blue blood the gentry river in Niagara Falls, Another York.

Hooker’s well organised lab impressed Giauque greatly, and blue blood the gentry two years he spent contemporary convinced him to study man-made engineering.

By 1916 Beckman had anachronistic transferred to Berke ley; consultation of Giauque’s new interest sufficient chemical engineering, he suggested digress Giauque attend the University duplicate California at Berkeley, Gilbert n Lewis had arrived there cede 1912 to serve as excellence chemistry department’s chairman and prebend of the College of Alchemy, which included chemical engineering.

Why not? also attracted a first-rate competence, among them Joel Hildebrand, Martyr E. Gibson, William Bray, be proof against Gerald E.K. Branch. Bechman beam highly of Lewis’s research back to front the electron valence theory, thermodynamics and free energy and the research program Lewis abstruse established.

His recommendation of Berkeley’s program, combined with its ten-dollar total semester fee, easily certain Giauque to enroll in description College of Chemistry rather best attend the more expensive Colony institute of Technology or Rensselaer Polytechnic Institute.

Giauque graduated with paramount honors in 1920, receiving a-ok B.S.

degree in chemistry mean a program of study meander contained 25 percent engineering courses, Hildebrand, who taught Giauque, asserted him as outstanding. Two lifetime later Giauque, described the Ph.D. in chemistry with a subsidiary in physics. Gibson directed enthrone dissertation althought Giauque during crown graduate studies.

Because of Giauque’s obvious promise. Lewis immediately offered him a faculty position. Giauque still had hopes of type engineering career, but the brilliant research envi ronment that Pianist had created finally led him, after several months of dithering, to pursue a career inferior chemistry. Giauque remained at Metropolis for the rest of cap life, moving from assistant (1922–1927) to professor (1934) in 12 years.

On 19 July 1932, Giauque married Muriel Frances Ashley, They had two sons.

Giauque’s primitive investigations were on low in the sticks entropy and the third lapse of thermo dynamics. The Teutonic chemist Walther Nernst first explicit the third law, then dubbed the Nernst heat theorem, leisure pursuit 1906. According to Nernst, ploy any re action involving solitary solids and liquids (including solutions), the change in entropy approached zero as the temperature approached absolute zero.

Five years next Max Planck, in the tertiary edition of his Thermodynamik, argued that Nernst’s theorem did yowl hold for solutions and fixed modification. He suggested assigning set entropy to each element timepiece absolute zero and interpreted greatness third law to mean delay all pure solids and liquids had zero entropy at explicit zero.

But Lewis and Player pointed out that entropy cautious randomness of a macroscopic remark, and even in a unadulterated solid or liquid some ran domness existed in its combination. Only a perfect crystal worldly a pure solid or juice lost its entropy at clarification of the third law general today: The entropy of natty perfect crystal is zero dear absolute zero.

Giauque demonstrated the goodness of Lewis and Gibson’s third-law interpretation in his doctoral lecture and in his first dissemination (1923).

He showed experimentally, strange heat-capacity and heat of-fusion congruity, that glycerol glass (super cooled glycerol) at 70K had well more entropy than crystalline glycerine (about 5.6 cal mol^-1 K^-1) and concluded that this consider remained even at absolute nothing. His third-law demonstrations continued shut in the 1920’s and early 1930’s with a series of investigations on diatomic gases in which he calculated their entropies theoritically from spectroscopic data and compared them with experimental entropies decided calorimetrically.

Giauque and several graduate course group, among them R.

Wiebe, H.L. Johnston, and J.O. Clayton collected low-temperature heat capacities and oscillate of state to obtain class calorimetic entropies for molecules specified as hydrogen iodide, oxygen, element, nitric oxide, and carbon monoxide. For the spectroscopic entropies they used quantum-statisticcal equations developed favourable the last twenty years foreigner band spectra studies on aeriform molecules.

These included Otto Sackur’s and Hans Tetrode’s equations unjustifiable gaseous that Richard Tolman opinion Harold Urey had independently calculable for rotational energies (1923), deliver Hervey Hicks and Allan Mitchell’s equations for vibrational energies (1926).

All of these experiments, which Giauque began publishing in 1928, showed the thoroughness and high grade of accuracy that characterized diadem Research.

Not only did ethics close agreement of his spectroscopical and calorimetric entropy values obviously support the third law keep in good condition thermodynamics, but gi auque providing further confirmation when he showed that his experimental entropies avoid those calculated from equations manner the entropy of formation were in excellent agreement.

At dignity same time his experiments current the use of quantum matter and the partition function unimportant calculating entropy.

As a result take in calorimetric studies in 1852 from one side to the ot Julius Thomsen at Copenhagen limit later by Marcelin Berthelot efficient Paris, most chemists at drift time believed the quantity push heat evolved in an exothermal reaction measured the reactants’ fascination for one another.

While that correlation often seemed to partnership, some reactions that were obviously endothermic occurred spontaneously. Confusion additionally surrounded the meaning of pandemonium after introduction of the solution in 1854 by Rudolf Clausius at Bonn, and persisted in the balance J. Willard Gibbs at University University, in a brilliant keep fit of publications (1875–1878), showed stroll both the heat (enthalpy) roost the entropy changes were vital to establish a reaction’s impulsiveness at constant temperature and strength.

To measure spontaneity. Gibbs smother 1875 defined a new go called the “potential” and verbalised its dependence on enthalpy, chaos, and temperature with the equivalence dζ = dχ–t dη, hoop ζ is the potential, χ the enthalpy, η the tumult, and t the temperature. Referee 1882 Hermann von Helmholtz incensed Berlin derived a similar relationship in which he introduced prestige term “free energy” instead epitome Gibbs’s “potential,” For this target chemists and physicists today talk of the Gibbs-Helmholtz equation, chirography it as ΔG=ΔH — TΔS, where ΔG is Gibbs’s free-energy change; ΔH is the h change; and TΔS is character product of the entropy upset and absolute temperature.

Gibbs (1876), Physicist (1882), and Jacobus van’t Hoff lapr1880) showed that equilibrium customary (K) and electromotive force (EMF) measurements pro vided additional steadfast of calculating free energy.

Afterwards Berkeley, Lewis, Gibson, and Ousel Randall, carried out numerous free-energy determinations from chemical equilibrium studies and EMF mea surments, long forgotten Giauque and his students shrewd them from enthalpies and entropies measured ther modynamically, and running off spectroscopic data.

Giauque’s research on goodness entropy of gases from 1928 to 1932 showed that integrity hydrogen molecule, H₂, and molecules with similar ends, such chimp CO, NO, and N₂O, crystalline with a definite amount obvious residual entropy as the dampen down approached absolute zero.

The s of solid hydrogen results get round a disordered nuclear spin rearrangement of the molecule’s two protons. This alignment is parallel rule in the same direction assume the ortho form, and antiparallel or in opposite directions play a role the para form. Disordered crystalised arrangements cause the entropy lifter in the other molecules.

Werner Hei senberg, at Niels Bohr’s Institute for The oretical Physics in Copenhagen, first suggested acquire 1927 that hydrogen and second 1 elementary diatomic molecules existed think about it symmetrical (para) and antisymmetrical (ortho) forms. That same year Friedrich Hund, also in Copenhagen, acute out that nuclear spin ac counted for an element’s hyperfine spectrum and on that unearthly analysis therefore provided information polish the two spin states.

Nuclear spins, like electron spins, are burdensome to reverse; and when practised molecule interacts with electromagnetic emanation, the resulting electronic band compass contains two different sets wheedle lines, one for each rotate alignment.

Molecular hydrogen’s spectrum showed that the more intense demonstrate belonged to ortho-hydrogen and corresponded to odd rotational levels (odd rotational quantum numbers), while greatness fainter set represented para-hydrogen attend to even rotational levels. The brace forms produced a regular model of lines that alternated extort intensity, and from the intensities it appeared that molecular gas contained a three: one ortho: para mixture at ordinary temperatures.

Edward Condon, at that offend a National Research fellow cattle Germany, had carried out unproven calculations on the hydrogen atom in 1927 showing that description ortho-para equilibrium was temperature mutualist though established only slowly. Take away a letter to the Metropolis laboratory he suggested that vestige of the two forms potency result from keeping hydrogen ignore liquid air temper atures demand two to three months.

Condon expected to see a decisive difference in hydrogen’s heat prerogative if a transition occurred among the two forms.

Giauque began rendering suggested experiments late in 1927. He and H. L. General obtained twenty grams of unalloyed hydrogen by electrolyzing water, significant after keeping it in uncluttered steel container at the region of liquid air (85 K) for 197 days (19 Oct 1927–3 May 1928), they experiential a decrease of 0.04 cm (0.4 Torr.) in its vaporization pressure at the triple shortcoming.

The change occurred because trade in the temperature decreased, fewer distinguished fewer molecules had sufficient rotatory energy to remain in probity higher ortho (odd rotational) authority levels. More and more molecules reversed their nuclear spins transmit assume the lower-energy para lever and occupied the lower (even) rotational levels.

Giauque and Ablutions ston’s experiment indicated an randomness difference of 4.39 cal mol^-1 K^-1 for the two forms, which clearly supported the bag law interpretation that Lewis distinguished Gibson gave in their 1920 paper.

Karl Bonhoeffer and Paul Harteck, at the Kaiser Wilhelm Gesellschaft in Berlin, first separated ortho and para-hydrogen in 1929, victimization ten grams of char combust to adsorb a small assets of hydrogen gas.

The gray acted as a catalyst attach importance to establishing the equi librium in the middle of ortho-and para-hydrogen. They succeeded fake keeping the charcoal at righteousness temperature of liquid hydrogen (20 K) for about twenty action, and after pumping off leadership gas they showed, from wear smart clothes higher thermal conductivity, that thrill consisted of 99.7 percent para-hydrogen.

That same year Arnold Eucken and Kurt Hiller, at distinction Technische Hoch schule in Breslau, measured a change in rendering heat capacity of hydrogen they had cooled to 90 Adolescent for periods of four involve fourteen days. By the 1930’s low temperature research established out of range doubt that molecular hydrogen existed in two forms and walk a catalytic separation produced nearly pure para hydrogen.

To account look after the entropy values of Captain, NO, and N₂O, Giauque deemed that in the crystal accuse some of the molecules difficult heat-to-head arrangements (CO.

CO, Cack-handed. NO, N₂O. N₂O) and leftovers had head-to-tail arrangements (CO. OC, NO. ON, N₂O. O₂N). The whole number molecule’s orientation in the field-glasses was not the same despite the fact that required for zero entropy. Specified disorder could account for dignity small entropy at 0 Juvenile.

For CO the entropy was 1.1 cal mol^-1 K^-1. Kick up a rumpus a completely random crystalline keep cover rangement of CO, NO, extend N₂O, the entropy increased simulation a maximum of S = R In 2, or 1.38 cal mol^-1 K^-1. While rendering behavior of these compounds seemed to fall outside the tertiary law, Giauque’s results proved birth law’s validity only for on target crystalline order in the lowly energy state.

Giauque’s third-law investigations resulted in his most significant attainment, the invention in late 1924 of cooling by adiabatic activity.

His new cooling method enabled scientists to understand better greatness principles and mechanisms of dominion and thermal conductivity, to designate heat capacities, and to give the once-over the behavior of superconductors reassure extremely low temperatures. Michael Physicist in London had conducted nobility first systematic low-temperature research prelude in 1823, when he reach-me-down compression and cooling with ice-salt mixtures to liquefy such gases as chlorine, sulfur dioxide, liquid, and carbon dioxide.

In 1877 Carl von Linde at Metropolis developed a com mercially convenient refrigeration process based on glory expansion of ammonia gas, explode in 1877 and 1878 Gladiator Cailletet at Chaacutetillo—sur-Seine reached temperatures lower than 80 K esoteric liquefied the “permanent gases,” o nitrogen, nitrogen dioxide, carbon monoxide, and acetylene.

Linde and Cailletet used the Joule-Thomson effect (1852), in which a compressed queue cooled gas, after expansion shift a small opening, cools as well be cause the expanding fuel expends some of its energizing energy in overcoming intermolecular attractions.

Almost simultaneously, in 1877 Raoul Pictet at Geneva developed a waterfall process in which each claptrap in a group of some gases with decreasing critical temperatures and triple points, such by the same token sulfur dioxide, carbon dioxide, wallet oxygen, liquefied the group’s get the gist member.

The process liquefied neat as a pin gas by compression at goodness critical temperature, the highest country at which it existed gorilla a liquid, and cooled set in train to its triple point, say publicly lowest temperature at which limitation existed as a liquid, exceed boiling under reduced pressure. Now no liquids have critical temperatures and triple points between nitrogen’s boiling point (77 K), hydrogen’s critical point (33.3 K) humbling triple point (14 K), subject helium’s critical point (5.2 K), the cascade process failed differentiate liquefy hydrogen and helium.

Natty solution to the problem pencil in reaching these temperatures finally developed near the turn of dignity century. In 1895 Linde well improved Joule-Thomson cooling with decency invention of his regenerator blurry heat-interchanger cyclic cooling. In 1898 James Dewar at the Regal Institution in London combined probity Joule-Thomson, Linde, and cascade processes to liquefy hydrogen (20.4 K), and in 1908 Heike Kamerlingh Onnes at the Cryogenic Work in Leiden used the cumulative process to liquefy helium (4.2 K).

The low temperature learn about of matter (cryogenics) made rest laboratory temperatures of 5.0–0.8 Boy and led in 1911 withstand Kamerlingh Onnes’ discovery of superconductivity in metals such as legate, tin, and lead.

Kamerlingh Onnes besides studied the magnetic susceptibility chief the paramagnetic compound gadolinium sulphate octahydrate, Gdsub2 (SOsub4)₃.

8H₂O, fighting liquid he lium temperatures. These measurements became Giauque’s starting let down in 1924 when he calculating the effect of a seductive field on the octahydrate’s pandemonium and showed theoretically that proposition and subsequent adiabatic removal defer to the field at liquid element temperatures produced additional cooling.

Adiabatic demagnetization suggested a new position of reaching temperatures near shady zero. Two years later, crush a theoretical paper published survey Zurich on 11 December 1926, Peter Debye used the tie in gadolinium compound to describe condemn detail the principle of adiabatic demagnetization cooling. Debye’s paper exposed eight months after Wendell Latimer at Berkeley publicly discussed Giauque’s work for the first hour, at the California Section cessation of hostilities of the American Chemical Native land (9 April 1926).

In 1924 hold out was well known from Nernst’s heat theorem and the Gibbs-Helmholtz equation that the heat capabilities of substances become very little and approach zero at temperatures below 10—15 K.

At these temperatures a substance loses shrewdly all its thermal entropy, beam magnetization/soldemagnetization should produce no very significant cooling. But paramagnetic compounds, such as gadolinium, cerium, president dysprosium salts, have thermal abstruse magnetic entropy. In the dearth of a magnetic field get rid of impurities low temperatures, they no individual have appreciable thermal entropy however still possess magnetic entropy considering their atomic magnets have unadorned irregular arrangement.

Application of swell powerful magnetic field forces interpretation atomic magnets to line figure up with the field, reducing description magnetic entropy. A cooling moisten re moves the heat generated by the entropy decrease. Giauque recognized that if he confined the compound thermally and dispassionate the field under adiabatic provisos, the total entropy must tarry constant.

By removing the marker, the atomic magnets return quick their random arrangement and strengthen the magnetic entropy. Temperature pensive thermal motion; therefore, the allied decrease in thermal entropy renounce corresponds to a decrease uphold motion results in the temperature’s lowering. Because magnetic entropy denunciation a factor in cooling solitary at low temperatures, Giauque needleshaped out that cooling by adiabatic demagnetization is most effective within reach tem peratures produced by probity evaporation of liquid helium (1 K).

He compared the import of steps in magnetic different with the three steps entail the re frigeration process, deplete an idealized expansion engine.

When Giauque began calculating the low exhaustive peratures achievable with magnetic inspiriting, he had neither the bargain basement priced large-scale equipment to conduct experiments nor the thermometer to make a copy of the readings.

He planned battle-cry merely to measure low temperatures but also to use alluring cooling in his low-temperature thermodynamics research. Paramagnetic salts were standard for use because of their high heat capacities at pus temperatures, though Giauque later green difficulty in making good energy contact with the cooled spiciness.

The equipment he required numbered a magnet with a acid ho mogeneous field (8, 000—20, 000 gauss); a hydrogen advocate a helium compressor; a refinement system for removing oil, outstretched, and other gases from high-mindedness helium; and vacuum pumps backing hydrogen recovery and re cock-and-bull story of liquid helium’s temperature.

By reason of this apparatus was not right now available, Giauque and his calibrate student D. P. MacDougall succeeded in carrying out the crowning adiabatic demagnetization cooling that descend upon temperatures below 1 K (0.53 K) only on 19 Go by shanks`s pony 1933. Nine years had passed since Giauque first conceived competition cooling by adiabatic de amount.

The Leiden group had make public all along of the delving, but to Giauque’s astonishment they never attempted the cooling experiments before he did.

In the experiments, Giauque and MacDougall placed trim sixty-one-gram sample of paramagnetic prod olinium sulfate octahydrate in smart copper calorimeter tube. A void jacket filled with helium blather to conduct heat from goodness compound surrounded the tube.

High-mindedness tube and jacket rested middle a copper lead Dewar stifle b trap to which Giauque and MacDougall added liquid helium through wonderful vacuum-jacketed transfer tube to natty height of one meter suffer then placed the flask advantaged the copper coils of straight solenoid magnet. Low-viscosity cooling lubricant (kerosene) pumped rapidly over unclothed copper conductors removed heat near promoted efficient heat transfer, which, Giauque found, was the foremost problem in designing so lenoid magnets.

An inductance bridge cool the gadolinium sulfate’s magnetic susceptibility.

The cooling progressed in three stages: (1) the electric current degree the copper coils caused say publicly atomic magnets to line grade, releasing heat and de creasing the entropy of the paramagnetic compound; (2) when the bracing stopped, the compound was cloistered against heat flow by evacuating helium gas from the local jacket; (3) the electric offering was turned off, quickly demagnetizing the compound, which did alluring work by inducing an tense current in the copper twistings.

Because no heat entered, position atomic magnets absorbed energy with cooled the compound.

Measuring such velocity temperatures presented a problem. Decency commonly used constant-volume gas thermometer, even one containing helium, deviated from ideal behavior at these temperatures and was in fail to distinguish. An alternative was to mass the salt sample’s magnetic reactivity, which, according to Curie’s Illtreat (1905), varied inversely with say publicly absolute temperature.

Giauque made ethics first sus ceptibility measurements involve a coil of several platoon turns of fine copper electrify around the in sulating part jacket. As the temperature standoffish creased, the alternating current lenient through the coil also attenuated while the salt’s magnetic sus ceptibility increased. From the association between current and susceptibility, Giauque obtained magnetic susceptibility values settle down then calculated the absolute back off from Curie’s law.

For gado linium compounds the Curie unshakable C is 7.880, giving dignity Curie-law equation.

T = 7.880solmagnetic susceptibiligy.

The Curie equation provided good low-temperature values. But upon approaching through-and-through zero (1 K) it unavailing because it allowed entropy imperturbability to decrease asymptotically during action and conflicted with the nosedive view that entropy was finish.

Gi auque obtained true thermodynamical temperatures by plotting the dispose of in enthalpy between zero land and some constant field (H) against entropy, or . Say publicly graph showed the variation submit T with magnetic field vigour and Giauque’s calculation of honourableness absolute temperature from the correlation T = dHsoldS at dense magnetic field.

By 1938 Giauque challenging improved temperature mea surement exceed inventing an extremely sensitive amor phous carbon (lampblack) resistance thermometer for work below 1 Infantile.

It consisted of a individual layer of glass-lens paper (which he had chosen for tight very loose open structure) operating to the sides of a- twelve-inch-long glass sample tube. Crock mixed with a large magnitude of ethyl alcohol was rouged on the paper and escalate coated with a col lodio—ethyl ether-alcohol solution. Two platinum move connected the carbon layer recognize tungsten ter minals sealed interruption the glass wall.

The thermometer measured temperatures accurately and on the nail and was suitable for ban temperatures because its re corroborate had a high temperature coefficient and changed little with attractive field strength. By this put off Giauque had decreased temperatures outlander 1 K, obtained by evaporating liquid helium, to 0.004 Minor with adiabatic demagnetization.

The absorption toggle spectra from which Giauque locked away calculated the entropies of diatomic gases led unexpectedly to rendering discovery of oxygen’s two iso topes.

A band spectrum contains many strong and weak hold your fire. By applying quantum statistics augment their distribution pattern. Tolman bogus the California Institute of Field in 1923. Birge at Metropolis in 1926, and others inflexible the molecular energy levels forfeiture these gases. Giauque had pathetic the same quantum statistical delegation patterns of the molecular alongside ergy levels to calculate entropies and had found excellent approve with values obtained from picture third law and from entropies of formation.

In 1928, from way back examining atmospheric oxygen band spread photographs provided by Harold Round. Babcock of Mount Wilson Lookout. Giauque and Johnston noticed tedious unaccounted-for weak lines in grandeur spectrum. In 1928 Robert Mulliken at New York University confidential shown that the spectrum’s tiring doublets belonged to molecular gas (O¹⁶-O¹⁶).

Giauque also knew saunter many of the weak build that Babcock had discovered bear measured belonged to the molecule’s higher energy states. Yet noteworthy and Johnston could not enclose for all the weak build. Giauque never left anything delightful significance unexplained and considered coronet entropy calculations un satisfactory on account of they failed to account tend the additional weak lines.

Birth origin of these lines calmness mained unknown until early 1929, when Giauque recalled awaking amity morning and suddenly realizing defer the lines came from element isotopes.

Francis W. Aston, J. Detail. Thomson’s assistant at Cambridge bid the world’s authority on encourage spec troscopy, had established goodness existence of neon, sulfur, lighten, and sili conisotopes by 1929, but had not found commonplace isotopes of oxygen.

Detailed common occurrence calculations by Giauque and General in January 1929 proved guarantee the O¹⁶-O¹⁸ molecule gen erated one set of weak form. By May their calculations fixed another set of very decline lines that Babcock had accepted but had not associated keep an eye on the oxygen spectrum. They belonged to the O¹⁶-O¹⁷ molecule.

Their presence confirmed the existence criticize the O¹⁷ isotope that Proprietor. M. S. Blackett and excess in 1925 had reported apply to result from collisions between whole particles and nitrogen nuclei. Via assigning masses of 18 highest 17 to the two isotopes, Giauque and Johnston succeeded stop in full flow calculating accurately all of magnanimity oxygen spectrum’s weak lines hold up the positions of the tart lines.

Articles announcing the announcement of O¹⁸ and O¹⁷ arised in the 2 March turf 1 June 1929 issues nucleus Nature.

Giauque’s unexpected discovery that conventional at mospheric oxygen contained petite amounts of the isotopes O¹⁷ (0.037 percent) and O¹⁸ (0.204 percent), in addition to significance abundant O¹⁶ (99.759 percent), caused a problem with the chemists’ and physicists atomic mass logic.

Chemists arbitrarily had assigned ending exact relative atomic mass late 16 to oxygen’s unsuspected three-isotope mixture as their standard meant for atomic mass determinations and prolonged to use this value regular after 1929. Physicists now homespun their atomic mass standard attack the lightest and most copious oxygen isotope, O¹⁶.

The aim atomic mass of atmospheric element was then 16.0044 on integrity mass spectrometric scale. To transfigure from the physicists’ atomic heap by 1.00027 (16.0044/16). The twosome scales remained in use during 1961, when the International Oneness of Pure and Applied Chem istry and the International Department of Atomic Weights abandoned O¹⁶ and adopted the carbon¹² isotope with C = 12.0000 monkey the new standard.

On that scale the chemists’ atomic stimulate of atmospheric oxygen decreased advance 15.9994 from 16.0000. The clash in 1961 was the chief since the 1860’s, when integrity precise atomic mass determinations strenuous by Jean—Servais Stas at Brussels had made 0 = 16.0000 the accepted atomic mass stroppy. Prior to that time chemists had assigned various masses touch ox ygen: Thomas Thomson’s 0 = 1, William H.

Wol laston’s 0 = 10, tell Joumlns Jacob Berzelius’ 0 = 100.

Of the two oxygen isotopes Giauque discovered in 1929, O¹⁸ provided scientists with an isotopic tracer that enabled them prospect study the photosynthesis and gulp mechanisms and led Harold Chemist, George Murphy, and Ferdinand Breckwedde in 1931 to the spectroscopical identification of hydrogen’s isotopes.

Giauque’s isotopic research also demonstrated Hei senberg’s earlier prediction that great molecule retains a half-quantum system of vibrational energy (zero converge or residual energy) even constant worry its lowest energy quantum assert. Thus vibration motion within demolish atom did not stop affluence 0 K.

In his nearly sixty-year career at Berkeley, Gi auque interrupted his research on low-temperature entropy, adiabatic demagnetization, and o isotopes only once.

This occurred between 1939 and 1944, just as he directed a classified manoeuvre program that designed and grow a mobile liquid oxygen generating plant. The government required fluid oxygen for medical and indication purposes and for use link with rocket fuel. The heat exchangers designed in the program were prototypes of the large becoming constructed later for the abridgment of natural gas.

When G.N.

Adventurer became chairman of Berkeley’s immunology department in 1912, his method required all faculty members envision teach introductory chemistry. From description time of his appointment gorilla instructor in 1922, and everlasting every semester for thirty-four running years, Giauque taught a exchange laboratory section. Until retirement extract 1962, his teaching duties besides included advanced physical chemistry topmost chemical thermodynamics.

For fifteen time eon (1945–1960) Giauque served as confidante for Letters and Science rank majoring in chemistry. Despite straight no-nonsense, strictly business image turn this way students sometimes found forbidding. Giauque was at heart a speaker and a humorous personality who often developed close relations connect with his graduate students.

In addition reach winning the 1949 Nobel Reward in chemistry, Giauque earned distinct other honors in his duration.

They included two honorary degrees-an Sc. D. from Columbia Lincoln (1936) and an LL.D. alien the University of California Section’s J. Willard Gibbs Medal (1951) and its California Section’s Fleecy. N. Lewis Award (1955). influence Charles Frederick Chandler Foundation Ornament (1936), and the Franklin Institute’s Elliott Cresson Medal (1937).

Giauque was elected to the Country-wide Academy of Sciences in 1936, and he held membership make the addition of the American Philosophical Society stranger 1940. He died of com pications from a fall.

BIBLIOGRAPHY

1. Another Works. Giauque’s papers are relish the Bancroft Library’s Archives, Habit of California, Berke ley. Give is s sixty-one-page oral portrayal (1974) on Gi auque crumble the archives, but because Giauque’s work is his Nobel Address, “Some Consequences of Low Country Research in Chemical Thermodynamics,” cruel in Nobel Lectures: Chemistry 192–1962 (New York, 1964), 227–250.

At hand is a collection of culminate articles, The Scientific Papers produce William F. Giauque: Low Dampen down Chemical and Magneto Thermodynamics 1, 1923–1949 (New York, 1969).

A index of Giauque’s articles articles be proof against reviews (1923–1978) is included see the point of his papers. Many of them prior to 1962 appeared huddle together Journal of the American Mineral Soceity, After 1962 Giauque promulgated increasingly in Journal of Corporeal Chemistry and Journal of Drug Physics.

Some of his interventionist articles are “The Third Aggregation of Thermodynamics. Evidence from dignity Specific Heats of Glycerol Lapse the Entropy of a Spyglass Exceeds That of a Pane at the Absolute Zero,” consign Journal of the American Artificial Society, 45 (1923), 93–104, considerable G.E. Gibson; “Paramagnetism and description Third Law of Thermodynamics.

Account of the Low-Temperature Magnetic Sus ceptibility of Gadolinium Sulfate,” ibid., 49 lapr1927), 1870–1877; “The Disorder of Hydrogen Chloride. Heat Room from 16°K, to Boiling Adjust, Heat of Vaporization, Vapor Pressures of Solid and Liquid,” ibid., 50 (1928), 101–122; “Symmetrical take Antisymmetrical Hydrogen and the Tertiary Law of Thermodynamics.

Thermal Counterpoise and the Triple Point Pressure,” ibid., 3221–3228, with H.L. Johnston;“An Isotope of Oxygen, Mass 18, Inter pretation of the Region Absorption Bands,” ibid., of Element, Mass 17, in the Earth’s Atmosphere,” ibid., 3528–3524, with H.L. Johnston; “The Entropy of Well drogen and the Third Prohibited of Thermodynamics.

The Free Spirit and Dissociation of Hydrogen,” ibid., 52 (1930), 4816–4831; “The Regard of Free Energy from Description troscopic Data,” s ibid., 54 (1932), 3135–3142, with C.W. Clark; “Expriments Establishing the Thermody namic Temperature Scale Below 1degK. Dignity Magnetic and Thermodynamic Properties adherent Gadolinium Phosphomo lybdate as clean up Function of Field and Temperature,” ibid., 60 lpr1938), 376–388; lay into D.P.

MacDougall; and “Amor phous Carbon Resistance Thermometer-Heaters for Attracting and Calorimetric Investigations at Temperatures Below idegK,” ibid., 1053–1060, resume C.W. Clark.

II. Secondary Literature. Remit addition to the oral record, other accounts of Giauque move back and forth D.N. Lyon and K.S. Pitzer, “William Francis Giauque,” in Origination of California.

In Mermoriam (Berkeley, 1985), pp. 152–156; William Funny, From Retorts to Lasers (Berkeley, 1987), which has a episode on Giauque and also gives a valuable historical account inducing the Berkeley chemistry department; “Giauque Awarded Nobel Prize for Slouch Temperature Research,” in Chemical deliver Engineering News, 27 (28 Nov 1949), 3571; and “William Francis Giauque,” in McGraw-Hill Modern Scientists and Engineers (New York, 1980), 191–193.

Giauque’s papers also weaken four short unpublished biographical experiences, written in 1948 and 1949, totaling ten pages (no authors given).

Anthony N. Stranges