题型:填空题 —I saw Kate in the park this morning.—It ______ her. She moved to Canada last week. A.can beB.must beC.can’t beD.mustn’t be 查看答案
题型:填空题 现有MgCl2和Al2(SO4)3混合溶液,向其中不断加入Na2O2,得到沉淀的量与加入Na2O2的物质的量如图所示,原溶液中Cl-与SO42-的物质的量之比为 ( )A.1:3B.2:3 C.6:1D.3:1 查看答案