In a permanent magnet at room temperature,

In the embryonic stage,$RBC$s develop in:

Two bar magnets $A$ and $B$ are placed one over the other and are allowed to vibrate in a vibration magnetometer. They make $20$ oscillations per minute when the similar poles of $A$ and $B$ are on the same side,while they make $15$ oscillations per minute when their opposite poles lie on the same side. If $M_A$ and $M_B$ are the magnetic moments of $A$ and $B$ and if $M_A > M_B$,the ratio of $M_A$ and $M_B$ is

In a saturated solution of $Mg(OH)_2$,the degree of dissociation of $Mg(OH)_2$ is $\alpha$. Find the concentration $(C)$ of $Mg(OH)_2$ if the concentration of $[OH^{-}]$ is $2$.

Two monoatomic ideal gases $1$ and $2$ of molecular masses $M_1$ and $M_2$ respectively are enclosed in separate containers kept at the same temperature. The ratio of the speed of sound in gas $1$ to that in gas $2$ is

Which one of the following molecular hydrides acts as a Lewis acid?