328:'s principal character, the physicist Viktor Shtrum, reflects on Prout's hypothesis about hydrogen being the origin of other elements (and the felicitous fact that Prout's incorrect data led to an essentially correct conclusion), as he worries about his inability to formulate his own thesis.
213:
times the mass of a hydrogen atom, with an error always less than 1%. This is a near miss to Prout's law being correct. Nevertheless, the rule was not found to predict isotope masses better than this for all isotopes, due mostly to mass defects resulting from release of
64:
when he succeeded in "knocking" hydrogen nuclei out of nitrogen atoms with alpha particles in 1917, and thus concluded that perhaps the nuclei of all elements were made of such particles (the hydrogen nucleus), which in 1920 he suggested be named
159:
claim that the basic unit was one-half of a hydrogen atom, but further discrepancies surfaced. This resulted in the hypothesis that one-quarter of a hydrogen atom was the common unit. Although they turned out to be wrong, these conjectures
111:
The discrepancy between Prout's hypothesis and the known variation of some atomic weights to values far from integral multiples of hydrogen, was explained between 1913 and 1932 by the discovery of
388:) accepted Rutherford's suggestion that the hydrogen nucleus be named the "proton," following Prout's word "protyle." Also cf. official report of this meeting, A.S. Eddington, 1920
287:
atoms (which have among the highest binding-energies) weigh only about 99.1% as much as 56 hydrogen atoms. The missing 0.9% of mass represents the energy lost when the nucleus of
430:
William Prout (1816). Correction of a mistake in the essay on the relation between the specific gravities of bodies in their gaseous state and the weights of their atoms.
373:
187:
with sufficient resolution to show that the two isotopic masses are very close to the integers 20 and 22, and that neither is equal to the known molar mass (20.2) of
283:(u), plus or minus binding energy discrepancy – atomic mass unit being the modern approximation for "mass of a proton, neutron, or hydrogen atom". For example
139:
Prout's hypothesis remained influential in chemistry throughout the 1820s. However, more careful measurements of the atomic weights, such as those compiled by
202:, in proportions such that the average weight of natural chlorine was about 35.45 times that of hydrogen. For all elements, each individual isotope of
702:
488:
463:
412:
William Prout (1815). On the relation between the specific gravities of bodies in their gaseous state and the weights of their atoms.
20:
697:
252:
is equal to sum of the masses of its constituent protons and neutrons, minus the mass of the nuclear binding energy, the
503:
74:
49:
that had been measured for the elements known at that time appeared to be whole multiples of the atomic weight of
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305:
717:
712:
73:
for particles, added to the stem of Prout's word "protyle". The assumption as discussed by
Rutherford was of a
292:
144:
518:"The Separation of Chlorine into Isotopes (Isotopic Elements) and the Whole Number Rule for Atomic Weights"
176:
53:. He then hypothesized that the hydrogen atom was the only truly fundamental object, which he called
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somehow trapped within thereby reducing the positive charge to +Z as observed and vaguely explaining
57:, and that the atoms of other elements were actually groupings of various numbers of hydrogen atoms.
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30:
155:, could not at the time be explained in terms of Prout's hypothesis. Some came up with the
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140:
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105:
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Report of the 88th meeting of the
British Association for the Advancement of Science
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435:
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of hydrogen into higher elements, it is now understood that atoms consist of both
452:
265:
253:
203:
199:
128:
92:. Such a nuclear constitution was known to be inconsistent with dynamics either
237:. The modern version of Prout's rule is that the atomic mass of an isotope of
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171:
was by 1919 suspected to be the result of the natural occurrence of multiple
419:
161:
561:
542:
29:
was an early 19th-century attempt to explain the existence of the various
195:
152:
148:
82:
50:
147:
in 1832, disproved the hypothesis. In particular, the atomic weight of
646:
Siegfried, Robert (1956). "The
Chemical Basis for Prout's Hypothesis".
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234:
172:
116:
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38:
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discovered multiple stable isotopes for numerous elements using a
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188:
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34:
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talks about turning elements into other elements of decreasing
33:
through a hypothesis regarding the internal structure of the
104:
hypothesis by
Rutherford and discovery by English physicist
16:
Early model of the atom that did not account for mass defect
264:, the mass of an isotope is roughly, but not exactly, its
580:
Gladstone, Samuel (1947). "William Prout (1785-1850)".
481:
The Oxford
Companion to the History of Modern Science
131:
of individual isotopes, with an error of at most 1%.
45:published two papers in which he observed that the
609:Benfey, O. Theodore (1952). "Prout's Hypothesis".
451:
374:British Association for the Advancement of Science
361:In a footnote to a 1921 paper by O. Masson in the
209:was eventually found to have a mass very close to
198:was found to be composed of the isotopes Cl and
8:
683:The Semiempirical Formula for Atomic Masses
506:Francis W. Aston, Nobel prize lecture 1922
483:. Oxford University Press. pp. 683–.
291:was made from hydrogen inside a star (see
551:
541:
225:Although all elements are the product of
372:281, 1921) Rutherford describes how the
405:
380:meeting beginning August 24, 1920 (see
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164:further measurement of atomic weights.
60:Prout's hypothesis was an influence on
479:John L. Heilbron (14 February 2003).
7:
127:, Prout's hypothesis is correct for
317:, until a gray matter is reached.
14:
703:Discoverers of chemical elements
100:but seemed inevitable until the
151:, which is 35.45 times that of
21:Progressive Utilization Theory
1:
648:Journal of Chemical Education
611:Journal of Chemical Education
582:Journal of Chemical Education
522:Proc. Natl. Acad. Sci. U.S.A
392:(John Murray: London) p. 34.
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18:
504:Mass spectra and isotopes
306:The Doings of Raffles Haw
194:By 1925, the problematic
183:. In 1919, Aston studied
37:. In 1815 and 1816, the
77:consisting of Z + N = A
19:Not to be confused with
293:stellar nucleosynthesis
167:The discrepancy in the
543:10.1073/pnas.11.10.624
363:Philosophical Magazine
233:(hydrogen nuclei) and
222:when they are formed.
175:of the same element.
698:History of chemistry
432:Annals of Philosophy
418:, 6: 321–330.
415:Annals of Philosophy
660:1956JChEd..33..263S
623:1952JChEd..29...78B
594:1947JChEd..24..478G
534:1925PNAS...11..624H
516:Harkins WD (1925).
434:, 7: 111–13.
256:. According to the
119:. According to the
320:In his 1959 novel
311:Arthur Conan Doyle
303:In his 1891 novel
299:Literary allusions
69:, from the suffix
27:Prout's hypothesis
668:10.1021/ed033p263
602:10.1021/ed024p478
490:978-0-19-974376-6
465:978-0-385-31211-0
258:whole number rule
181:mass spectrograph
121:whole number rule
62:Ernest Rutherford
31:chemical elements
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708:1810s in science
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281:atomic mass unit
241:(atomic number)
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718:1816 in science
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448:Lederman, Leon
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382:meeting report
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338:Binding energy
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247:neutron number
227:nuclear fusion
216:binding energy
169:atomic weights
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106:James Chadwick
47:atomic weights
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262:Francis Aston
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239:proton number
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129:atomic masses
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43:William Prout
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279:) times an
266:mass number
254:mass defect
204:mass number
177:F. W. Aston
143:in 1828 or
692:Categories
367:Phil. Mag.
344:References
87:beta decay
458:. Delta.
400:Citations
349:Footnotes
162:catalyzed
135:Influence
96:or early
94:classical
83:electrons
562:16587053
450:(1993).
332:See also
235:neutrons
196:chlorine
173:isotopes
153:hydrogen
149:chlorine
115:and the
113:isotopes
51:hydrogen
41:chemist
23:(PROUT).
656:Bibcode
639:4066298
619:Bibcode
590:Bibcode
553:1086175
530:Bibcode
378:Cardiff
376:at its
285:iron-56
231:protons
117:neutron
102:neutron
98:quantum
81:plus N
79:protons
75:nucleus
67:protons
55:protyle
39:English
637:
560:
550:
487:
462:
157:ad hoc
635:S2CID
191:gas.
71:"-on"
558:PMID
485:ISBN
460:ISBN
384:and
289:iron
245:and
189:neon
185:neon
35:atom
664:doi
627:doi
598:doi
548:PMC
538:doi
370:41,
295:).
218:in
123:of
694::
662:.
652:33
650:.
633:.
625:.
615:29
613:.
596:.
586:24
584:.
556:.
546:.
536:.
526:11
524:.
520:.
324:,
309:,
200:Cl
108:.
670:.
666::
658::
641:.
629::
621::
604:.
600::
592::
564:.
540::
532::
493:.
468:.
277:N
273:Z
271:(
269:A
250:N
243:Z
211:A
207:A
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