Mercury(I) ions (Hg22+) can be removed from solution by

Solution: Step1: a) In order to calculate the volume of 0.115 M HClO , we will use the 4utralization equation, i.e., M V1 M1V , 2e2 M and V are1 e molar1y and volume of the acid and M , V are the molarity and volume of the base. 2 2 Substituting the values of molarity and volume of the acid and base in the above equation, we get, 0.115 M X V = 0.0875 M X 50 mL 1 0.115 M X V = 4.31 (M X mL) V1 4.375 / 0.115 [(M X mL)/ mL] V1 38.04 mL Thus, required volume of HClO is 38.04 mL4 Step2: b) Mass of Mg(OH) = 2.87 g 2 Molar mass of Mg(OH) = 58.32 g/mol 2 Therefore, number of moles of Mg(OH) = 2.87 / 58.322 = 0.049 mol The reaction between HCl and Mg(OH) takes place in 2e following manner: 2HCl(aq) + Mg(OH) -----------> MgCl (aq) + 2H O 2 2 2 In the above equation, it is seen that, 1 mole of Mg(OH) requires 2 mole2of HCl for complete neutralization. Therefore, 0.049 moles of Mg