Question

Which of the following are correct about the subatomic particles found in ${}^{37}{Cl}^{-}$?
i. 21 neutrons
ii. 17 protons
iii. 16 electrons

• A. ii only
• B. iii only
• C. i and ii only
• D. i and iii only
• E. ii and iii only

Answer 1

The correct option is A ii only

i. Atomic number of Cl is 17, so no of protons are 17.
ii. With -1 charge the no of electrons are $17+1=18$.
iii. No of neutrons is (mass no - no of protons), i.e., $37-17=20$ neutrons.
So, only statement ii is correct.