Question

what mass of water will be produced from 9.6g of calcium hydroxide reacting with HCl

Answer 1

$$Ca(OH)_2 + 2HCl = CaCl_2 +2H_2O$$

$$n(Ca(OH)_2) = m/M = 9.6g/74(g/mol) = 0.13 mol$$

$$n(H_2O) = 0.13mol*2 = 0.26 mol$$

$$m(H_2O) = nM = 0.26mol*18(g/mol) = 4.7 g$$