Which of the following are true for an element?- Atomic number = number of protons + number of electrons
- Mass number = number of protons + number of neutrons
- Atomic mass = number of protons = number of neutrons
- Atomic number = number of protons = number of electrons
(a) (i) and (ii)
(b) (i) and (iii)
(c) (ii) and (iii)
(d) (ii) and (iv)
Correct Answer: (d) (ii) and (iv)
Explanation: Mass number is the sum of the protons and the neutrons. Atomic number is equal to the number of protons.
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