Which of the following are true for an element?
(i) Atomic mass = number of protons + number of electrons
(ii) Mass number = number of protons + number of neutrons
(iii) Atomic mass = number of protons = number of neutrons
(iv) Atomic number = number of protons = number of electrons
1
(i) and (ii)
2
(i) and (iii)
3
(ii) and (iii)
4
(ii) and (iv)