試題詳解

50.某一自來水含 200mg/L (as CaCO₃)鹼度，pH 值為 7.5，經由 H₂CO₃ 之解離式子與其解離常數計算得知 ［CO₃^2-］= 5.93×10^-6 (eq/L)，［HCO₃^-］=3.99×10^-3 (eq/L)，則其 M 鹼度為多少？
(A) 0.18 (mg/L as CaCO₃)
(B) 12.9 (mg/L as CaCO₃)
(C) 31.6 (mg/L as CaCO₃)
(D) 199.5 (mg/L as CaCO₃)