Question

Atom A has a mass number 209 and atomic number 82.
Atom B has a mass number 209 and atomic number 83.
(i) How many protons atom A has ?
(ii) How many protons atom B has ?
(iii) Are atoms A and B isotopes of the same element ?

Answer 1

Atom A – `""^209"A"_82`
Atom B –  `""^209"A"_83`
(i) A has 82 protons as the atomic number is 82.
(ii) B has 83 protons as the atomic number is 83.
(iii) No, A and B are not isotopes of each other because their atomic numbers are not same.