The number of molecules in $4.25 \ g$ of ammonia is approximately

The molar mass of $CO_2$ is $44 \ g/mol$. Given that the Avogadro constant is $6.022 \times 10^{23} \ mol^{-1}$,the mass of one molecule of $CO_2$ is ..... $\times 10^{-23} \ g$.

What is the number of moles of water molecules present in a mole of carnallite?

Arrange the following in order of increasing mass:
$I$. $1$ mole of $N_2$
$II$. $0.5$ mole of $O_3$
$III$. $3.011 \times 10^{23}$ molecules of $O_2$
$IV$. $0.5$ gram atom of $O$

Find out the total number of electrons present in $1.6 \ g$ of methane $(CH_4)$?

The mass of $1$ mole of electrons is .......