The number of moles of $BaCO_3$ which contain $1.5$ moles of oxygen atoms is:

The total number of molecules of $SO_2Cl_2$ in $13.5 \ g$ of sulfuryl chloride is ..... (in terms of $N_A$) (in $N_A$)

The number of moles in $620 \ g$ of sodium oxide is ..... moles.

The number of sodium atoms in $2 \ mol$ of sodium ferrocyanide $Na_4[Fe(CN)_6]$ is .......... $\times 10^{23}$. (Given $N_A = 6.022 \times 10^{23} \ mol^{-1}$)

What is the approximate weight of one molecule of methane $(CH_4)$?

Find the maximum number of atoms in the following:
$(i)$ $1 \ g$ $Au_{(s)}$
$(ii)$ $1 \ g$ $Na_{(s)}$
$(iii)$ $1 \ g$ $Li_{(s)}$
$(iv)$ $1 \ g$ $Cl_{2(g)}$