Question

A chlorine atom whose nucleus contains $17$ protons and $20$neutrons. Find out the composition of the nucleus of an isotope of chlorine?

• A. $20$ protons, $17$ neutrons
• B. $19$ protons, $18$ neutrons
• C. $18$ protons, $18$ neutrons
• D. $17$ protons, $19$ neutrons
• E. $16$ protons, $20$ neutrons

Answer 1

The correct option is D $17$ protons, $19$ neutrons

Isotope nucleus means that those nucleus has same protons number but different neutrons and mass number. Since chlorine has 17 protons so its isotope also will have 17 protons. Thus, option D will correct.