How much hydrogen is required to obtain 365 g of hydrogen chloride?

The reaction of obtaining hydrogen chloride: H2 + Cl2 = 2HCl.
1) According to the periodic table, we find the molar mass of hydrochloric acid: 1 + 35.5 = 36.5.
2) Find the amount of hydrochloric acid substance. To do this, divide the mass of the acid by the molar mass: 365 / 36.5 = 10 mol.
3) According to the reaction equation, there is one mole of hydrogen per two moles of hydrochloric acid. This means that the amount of hydrogen substance is: 2 * 10 = 20 mol.
4) Molar mass of hydrogen: 1 * 2 = 2.
5) Find the mass of hydrogen. To do this, we multiply the amount of hydrogen substance by its molar mass: 2 * 20 = 40g – the answer.