The $pH$ of water is $7$. When a substance $Y$ is dissolved in water,the $pH$ becomes $13$. The substance $Y$ is a salt of

Which of the following is true in the case of an adiabatic process,where $\gamma = C_p / C_V$?

An object takes $n$ times as much time to slide down a $45^{\circ}$ rough inclined plane as it takes to slide down a perfectly smooth inclined plane of the same inclination. The coefficient of kinetic friction between the object and the rough incline is given by:

If $\tan ^{-1} a+\tan ^{-1} b+\tan ^{-1} c=\pi$,then which of the following statements is true?

Which of the following compounds is consumed during the preparation of $Na_2CO_3$ by Solvay's process?

$CH_3-CH_2-CH=O$ $\xrightarrow[(2) H^{+}]{(1) \text{Tollen's reagent}} X$ $\xrightarrow[(2) \text{dry distillation}]{(1) Ca(OH)_2} Y$
$Y$ is: