They ________ about eight hundred English words by the end of last term. A.will learn B.had learned C.are going to learn D.have learned 答案:B
有镁铝合金10.2 g,溶于4 mol·L-1的盐酸500 mL里,若加入2 mol·L-1氢氧化钠溶液,使沉淀达到最大量,则需加入此种NaOH溶液为
A.
1 000 mL
B.
500 mL
C.
100 mL
D.
1 500 mL