A nucleus of mass number A and atomic number Z contains MCQ with Answer and Explanation

A nucleus of mass number A and atomic number Z contains
A. Z protons and A neutrons
B. A-Z protons and Z neutrons
C. Z protons and A-Z neutrons
D. A protons and Z neutrons
Answer: Option C
Solution (By JKSSB Mock Tests)
Atomic number Z = number of protons. Mass number A = protons + neutrons. So neutrons = A - Z. Electrons = Z in neutral atom. Isotopes same Z, different N.

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