Question

calculate the number of hydrogen atoms in 0.25 moles of sulphuric acid

Answer 1

You can multiple the following

6.02 x 10(23) molecules per mole times 0.25 moles. You will get 1.505 x 10(23) molecules.

Answer 2

$no. \: of \: particles \: \\ = n \times 6.022 \times {10}^{23} \times 2$
So, 0.25 = 1/4,
$\frac{1}{4} \times 6.022 \times {10}^{23} \times 2$
$= \: 3.011 \times {10}^{23}$