In the following reaction,$X$ and $Y$ are respectively:
$CH_3COOH + NH_3$ $\longrightarrow X \stackrel{\Delta}{}$ ${\longrightarrow} Y + H_2O$

With an increase in atomic number,the melting point of alkali metals .......

There are two coils $A$ and $B$ as shown in the figure. No current flows in $B$ if $A$ is at rest. Now,the coil $A$ is made to rotate about a vertical axis. At the shown instant $(t = 0)$,what will be the direction of the current in coil $A$ if the induced current in coil $B$ is counterclockwise?

If the sum of the deviations of $50$ observations from $30$ is $50$,then the mean of these observations is

Which of the following facilitates the opening of the stomatal aperture?

The graph which represents the variation of mean kinetic energy of molecules with temperature $t^{\circ}C$ is