What is the number of moles of $N$ atoms and number of moles of $O$ atoms respectively present in one mole of uracil?

Which one of the following will have the largest number of atoms?
$(i)$ $1 \,g$ $Au_{(s)}$
$(ii)$ $1 \,g$ $Na_{(s)}$
$(iii)$ $1 \,g$ $Li_{(s)}$
$(iv)$ $1 \,g$ of $Cl_{2(g)}$

The number of hydrogen atoms present in $5.4 \ g$ of urea is : (Given : Molar mass of urea: $60 \ g \ mol^{-1}$, $N_{A} = 6.022 \times 10^{23} \ particles \ mol^{-1}$)

If $3.01 \times 10^{20}$ molecules are removed from $98 \ mg$ of $H_2SO_4$,then the number of moles of $H_2SO_4$ left are:

The number of molecules and moles in $2.8375 \ L$ of $O_2$ at $STP$ are respectively

The number of moles of $Mg_3(PO_4)_2$ containing $0.25$ moles of oxygen atoms is: