Question

If 20 g of lithium is reacted with 98 g of H2SO4 how much hydrogen gas will be produced?

Answer 1

n Li = m Li / Mr Li

n Li = 20 / 7

n Li = 2.86 mol

n H2SO4 = m H2SO4 / Mr H2SO4

n H2SO4 = 98 / 98

n H2SO4 = 1 mol

H2SO4 is the limiting reactant

n H2 = (coef. H2 / coef. H2SO4) • n H2SO4

n H2 = (1/1) • 1

n H2 = 1 mol

m H2 = n H2 • Mr H2

m H2 = 1 • 2

m H2 = 2 gr