74g of calcium hydroxide will yield OH ions:

Explanation

74g of Ca(OH)2 equals 1 mole since the molar mass is 74 g/mol. The dissociation of Ca(OH)2 produces 2 moles of OH ions for every mole of Ca(OH)2. Each OH ion has a molar mass of 17g/mol, so 2 moles produce 34g of OH ions (17g/mol x 2). Thus, the correct answer is 34g. Options 178g, 51g, and 40g do not match the stoichiometric calculation for the amount of hydroxide ions produced from the dissociation of 74g of Ca(OH)2.