Answer to Question #340966 in Inorganic Chemistry for Calleb

Question

5g of calcium carbonate was strongly heated to a constant mass calculate the mas of the solid residue formed Ca=40.0,O=16.0,C=12

Answer 1

Solution:

The molar mass of calcium carbonate (CaCO₃) is (40 + 12 + 3×16) = 100 g/mol

Therefore,

Moles of CaCO₃ = (5 g CaCO₃) × (1 mol CaCO₃ / 100 g CaCO₃) = 0.05 mol CaCO₃

Balanced chemical equation:

CaCO₃(s) → CaO(s) + CO₂(g)

Thus, the solid residue is calcium oxide (CaO)

According to stoichiometry:

1 mol of CaCO₃ produces 1 mol of CaO

Thus, 0.05 mol of CaCO₃ produce:

(0.05 mol CaCO₃) × (1 mol CaO / 1 mol CaCO₃) = 0.05 mol CaO

The molar mass of calcium oxide (CaO) is (40 + 16) = 56 g/mol

Therefore,

Mass of CaO = (0.05 mol CaO) × (56 g CaO / 1 mol CaO) = 2.8 g CaO

Mass of CaO = 2.8 g

Answer: The mas of the solid residue (CaO) is 2.8 grams