Which of the following orders is correct for the heat of hydrogenation of these compounds?

Which of the following is not a greenhouse gas?

Select the incorrect pair:

If $A$ is a $3 \times 4$ matrix and $B$ is a matrix such that $A'B$ and $BA'$ are both defined,then $B$ is of the type:

$A$ photon of energy $8\,eV$ is incident on a metal surface of threshold frequency $1.6 \times 10^{15}\,Hz$. The maximum kinetic energy of the emitted photoelectrons is ...............$eV$ $(h = 6.6 \times 10^{-34}\,Js)$.

The $24$ hour (diurnal) rhythm of our body,such as the sleep-wake cycle,is regulated by the hormone: