第14题: [单项选择]How long does Jim have to stay in Tokyo A. One hour. B. Two hours. C. Three hours. 参考答案:B 答案解析:[听力原文] F: Do you have to change planes in Tokyo, Jim M: Certainly. We arrive there at ten an
第24题: [单项选择]0.3mmol/L(以当量粒子计)的.Mg2+换算为( )。 A. 10mgCaCO3/L B. 5mgCaCO3/L C. 7.5mgCaCO3/L D. 15mgCaCO3/L 参考答案:D 答案解析:要掌握当量粒子概念及当量粒子的摩尔质量。0.3mmol/L(以当量粒子计)的Mg2+也即0.3mmol/L(以当量粒子计)的CaCO3。CaCO3