The chemical symbol for nitrogen gas is

The molecular formula of aluminium sulphate is

Which of the following has the maximum number of atoms?

$(a)$ Calculate the number of moles in $112 \, g$ of iron.
$(b)$ Calculate the mass of $0.5$ mole of sugar $(C_{12}H_{22}O_{11})$.
$(c)$ Calculate the number of atoms in $8 \, g$ of oxygen $(O_2)$ molecules.
(Atomic mass of $Fe = 56 \, u, C = 12 \, u, H = 1 \, u, O = 16 \, u, N_A = 6.022 \times 10^{23} \, mol^{-1}$)

Which of the following has the maximum number of atoms?

In photosynthesis,$6$ molecules of carbon dioxide combine with an equal number of water molecules through a complex series of reactions to give a molecule of glucose having a molecular formula $C_6H_{12}O_6$. How many grams of water would be required to produce $18\, g$ of glucose? Compute the volume of water (in $cm^3$) so consumed assuming the density of water to be $1\, g\, cm^{-3}$.