Chemistry - AQA GCSE: 12 g of magnesium reacts completely with excess hydrochloric acid to form magnesium chloride and hydrogen:

Mg(s) + 2HCl(aq) → MgCl2(aq) + H2(g)

Calculate the maximum mass of hydrogen that can be produced. (Ar of Mg = 24, Mr of H2 = 2)

Question

12 g of magnesium reacts completely with excess hydrochloric acid to form magnesium chloride and hydrogen:

Mg(s) + 2HCl(aq) → MgCl2(aq) + H2(g)

Calculate the maximum mass of hydrogen that can be produced. (Ar of Mg = 24, Mr of H2 = 2)

Miqdaam Hamed Hassan · Accepted Answer

Amount of magnesium = mass ÷ rfm

Amount of magnesium = 12/24

= 0.5 mol

Looking at the equation, 1 mol of Mg forms 1 mol of H2, so 0.5 mol of Mg forms 0.5 mol of H2

Mass of H2 = Mr × amount

= 2 × 0.5

= 1 g

12 g of magnesium reacts completely with excess hydrochloric acid to form magnesium chloride and hydrogen: Mg(s) + 2HCl(aq) → MgCl2(aq) + H2(g) Calculate the maximum mass of hydrogen that can be produced. (Ar of Mg = 24, Mr of H2 = 2)