Calculate the mass of calcium hydroxide ca(oh)2 present in 100cm3 of a 0.1mol/dm^3 solution?

Molar mass of Ca(OH)₂ = (40.1 + 16×2 + 1.0×2) g/mol = 74.1 g/mol

Moles of Ca(OH)₂ = (0.1 mol/dm³) × (100/1000 dm³) = 0.01 mol
Mass of Ca(OH)₂ = (0.01 mol) × (74.1 g/mol) = 0.741 g

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OR:

(0.1 mol Ca(OH)₂ / 1000 cm³) × (100 cm³) × (74,1 g Ca(OH)₂ / 1 mol Ca(OH)₂)
= 0.741 g Ca(OH)₂