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10-08-2018
Physics

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How many neutrons does element X have if its atomic number is 39 and its mass number is 79?

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Supernova Supernova

10-08-2018

Number of neutrons: atomic mass - atomic number

Element X's atomic mass is 79 and its atomic number is 39. Subtract 39 from 79 to find how many neutrons Element X has.

79 - 39 = 40

Element X has 40 neutrons.

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