Calcium weighing 120 g reacts with phosphoric acid. Find the volume of hydrogen.

Let’s execute the solution:
1. Let us write down the equation and data according to the condition:
m = 120 g. X l. -?
3Ca + 2H3PO4 = Ca3 (PO4) 2 + 3H2 – OBP, obtained calcium phosphate, hydrogen;
2. Calculation of the molar masses of substances:
M (Ca) = 40 g / mol;
M (H2) = 2 g / mol.
3. Determine the number of mol Ca, H2:
Y (Ca) = m / M = 120/40 = 3 mol;
3 mol (Ca) – X mol (H2);
3 moles – 3 moles from here. X MOL (H2) = 3 mol.
4. Find the volume of hydrogen by applying Avogadro’s law:
V (H2) = 3 * 22.4 = 67.2 liters.
Answer: the product of the reaction hydrogen is released in a volume of 67.2 liters.