5- A water sample has a total alkalinity of 220mg/ and has a pH of 7.4. The maximum amount of calcium ion is found when the solubility product of CaCO3,Ks=[Ca++] [CO3]=4.57109, is met. For natural water, [HCO3]=1+2k2/[H+]Talk+[H+]kw/[H+][CO3]=2(1+[H+]/2k2)Talk+[H+]kw/[H+]k2=[H+][CO3]=[H+][OH3][HOO3]=4.691011 Calculate the maximum amount of calcium ion in mg/l as CaCO3 that could be contained in a solution at equilibrium at 25C