MCQ : Which of the following is true? [A = mass number, Z = atomic number, N = number of neutron]

Question

Which of the following is true? [A = mass number, Z = atomic number, N = number of neutron]

1. A = Z
2. A = Z-N
3. A = Z+N
4. A = N – Z

Answer

A = Z + N

Explanation

The relationship between the mass number (A), atomic number (Z), and number of neutrons (N) is A = Z + N. The mass number represents the total number of protons and neutrons in the nucleus of an atom, while the atomic number represents the number of protons. The number of neutrons can be calculated as N = A – Z.