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Sami Rizk

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330. kalic CZ 3
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What number goes into the empty square?
MATH PUZZLE: Can you replace the question mark with a number?
MATH PUZZLE: Can you replace the question mark with a number?


In 1933, Ernest Rutherford suggested the names diplogen for the newly discovered heavy hydrogen isotope and diplon for its nucleus. He presented these ideas in the Discussion on Heavy Hydrogen at the Royal Society. For ordinary hydrogen, the lightest of the atoms, having a nuclues of a sole proton, he coined a related name: haplogen. (Greek: haploos, single; diploos, double.) In 1931, Harold Urey had discovered small quantities of atoms of heavy hydrogen wherever ordinary hydrogen occurred. The mass of its nucleus was double that of ordinary hydrogen. This hydrogen-2 is now called deuterium, as named by Urey (Greek: deuteros, second). Its nucleus, named a deuteron, has a neutron in addition to a proton.[ref: Proc. Roy. Soc. A, vol. 144 (1934)]

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