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Calculate the number of neutrons present in the nucleus of an element X which is represented as 31X15
Mass number (A) = No. of protons (Z) + No. of neutrons
Given, mass number = 31
No. of protons = 15
No. of protons (Z) + No. of neutrons = 31
No. of neutrons = 31 – number of protons
No. of neutrons = 31 – 15 = 16.
Hence, the No. of neutrons =16.
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