From $392 \, mg$ of $H_2SO_4$,$1.204 \times 10^{21}$ molecules are removed. How many moles of $H_2SO_4$ are left?

The number of water molecules present in a drop of water weighing $0.018 \ g$ is

Identify the number of moles of $H$ atoms present in $n$ moles of the organic compound represented as: (in $n$)

What is the number of moles of sulfur atoms present in $n$ mole molecules of mustard gas?

The mass of $0.1 \ mol$ of methane $(CH_4)$ is .......... $g$.

$A$ thin layer of cobalt is deposited on a plate with a total area of $0.5 \ m^2$ and a thickness of $0.005 \ cm$. How many cobalt atoms are deposited on the plate? (Density of cobalt $= 8.9 \ g \ cm^{-3}$,Atomic mass of $Co = 59 \ g \ mol^{-1}$)