The number of pi-bonds present in benzoic acid molecule are

The elevation in boiling point of 0.25 molal aqueous solution of a substance is $\left(K_o=0.52 \mathrm{~K} \mathrm{~kg} \mathrm{~mol}^{-1}\right)$

The combining ratios of hydrogen and oxygen in water and hydrogen peroxide are $1: 8$ and $1: 16$. Which law is illustrated in this example?

If a metal crystallises in bcc structure with edge length of unit cell $4.29 \times 10^{-8} \mathrm{~cm}$ the radius of metal atom is