Find the number of electrons present in $34 \ g$ of $NH_{3(g)}$. (Express your answer in terms of $N_A$)

Find the volume at $STP$ and mass of $6.022 \times 10^{23}$ molecules of $O_2$. (Molar volume $= 22.4 \ L$)

The number of molecules in $4.25 \, g$ of ammonia is:

In a flask,the weight ratio of $CH_{4(g)}$ and $SO_{2(g)}$ at $298 \ K$ and $1 \ bar$ is $1:2$. The ratio of the number of molecules of $SO_{2(g)}$ and $CH_{4(g)}$ is

Number of atoms in the following samples of substances is largest in

The total number of valence electrons in $4.2 \ g$ of $N_3^-$ ion is ............. $N_A$ ($N_A$ is the Avogadro's number).