Which from following species does not have number of electrons similar to other three species?

What is the name of tert-butyl alcohol according to carbinol system?

Identify the element having outer electronic configuration $\mathrm{ns}^2 \mathrm{np}^5$.

What is the mass in kg of 5 mole of acetic acid $\left(\mathrm{mol}\right.$. mass $\left.=60 \mathrm{~g} \mathrm{~mol}^{-1}\right)$ ?