Question

A solution is prepared by dissolving 0.0034 g Ca(OH)2 in enough water to prepare a 250 mL solution. what is the pH of the solution if Ca(OH)2 completely dissociates producing 2 OH for every 1 Ca

Answer 1

Molaro mass of Ca(OH) = 74.092 g/mol Numbers of moles of CaCOH & Weight . molars mass 0.0034 g 74.092 g farol - 4.58× 10-5 mol Molasity of Ca(OH), Solution - numbers of moles volume in litroe 4.58× 105 mol 250 x 10-3 L = 1.83 x 10-4 mol/L Ca(OH)2 (aq) - Cart (aq) + 2 OH (aq) concentration of otion = (2x 1.83× 10 -4 ) mol/L . - 3.66x 10-4 mol/l pOH = -log [OH- ] =- log (3.66 x 10^) - 3.43

.: pH = 14-POH = 14 -3.43 = 10.57