Chemistry - Mole Concept Question with Solution | TestHub

No. of moles of a compound $=\frac{\text{ given mass }(\mathrm{gm})}{\text{ Molar mass }(\mathrm{gm})}$ i.e. $\frac{25.6}{342.3}=0.0748$ moles. 1 mole of sucrose $\left({\mathrm{C}}_{12}{\mathrm{H}}_{22}{\mathrm{O}}_{11}\right)$ contains $6.022$ $\times 10^{23}$ molecules of it. Hence $0.0748$ moles contains $\begin{array}{l}=6.022\times 10^{23}\times 0.0748\\ =0.4504\times 10^{23}\text{ molecules. }\end{array}$ 1 molecule of sucrose by formula is having 22 atoms of hydrogen. $\therefore 0.4504\times 10^{23}\times 10^{23}\times 22=9.91\times 10^{23}$ atoms of hydrogen.