The mass of salt formed during the dissolution of copper (II) oxide with a mass of 20 g in excess of sulfuric acid is

Compose a reaction equation
CuO + H2SO4 = CuSO4 + H2O
Calculate the amount of substance of copper oxide (CuO) 20 g / 79.5 g / mol = 0.25 mol
Calculate the amount of substance of salt (CuSO4) = 0.25 mol (equal to the amount of substance of copper oxide)
Calculate salt mass m (CuSO4) = M * n (amount of substance) = 159.5 g / mol * 0.25 mol = 40 g

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