What mass in grams of hydrogen is produced by the reaction of 31.3 g of magnesium with 2.12 g of water?
Mg (s) + 2H₂O (l) → Mg(OH) ₂(s) + H₂(g)

Question

What mass in grams of hydrogen is produced by the reaction of 31.3 g of magnesium with 2.12 g of water? Mg (s)+ 2H₂O (l)→ Mg(OH)₂(s)+ H₂(g) A)0.119 B)0.237 C)0.474 D)0.0593 E)2.71

Quizplus · Accepted Answer

The balanced chemical equation is:Mg (s)+ 2H₂O (l)→ Mg(OH)₂(s)+ H₂(g)31.3 g of magnesium react with 2.12 g of water to produce hydrogen gas.The molar mass of magnesium is 24.31 g/mol.The molar mass of water is 18.02 g/mol.The molar mass of hydrogen is 2.02 g/mol.The number of moles of magnesium is 31.3 g / 24.31 g/mol = 1.29 mol.The number of moles of water is 2.12 g / 18.02 g/mol = 0.118 mol.The mole ratio of magnesium to hydrogen is 1:1.Therefore, the number of moles of hydrogen produced is 1.29 mol.The mass of hydrogen produced is 1.29 mol * 2.02 g/mol = 2.61 g.

What Mass in Grams of Hydrogen Is Produced by the Reaction