题目

现有H2 SO4、BaCl2、NaOH、Na2CO3、MgSO4、Ca(OH)2五种溶液和一种气体CO2，有图1所示的相互反应关系，图中每条连线表示两端的物质可以发生化学反应，试将它们的化学式填入图1中相应的六个方框中。 答案：【解析】可先找出物质间的全部相互反应关系，如图2。完成句子阅读下列各小题，根据汉语提示完成句子；每空一词。1.The newly-opened supermarket had something on sale last Sunday. (改为一般疑问句)______ the newly-opened supermarket ______ anything on sale last Sunday?2.They will study abroad after they finish high school. (改为同义句)They won’t study abroad ______ they ______ high school.3.他们一大早就动身去伦敦旅行了。They ______ ______ for London on a holiday early in the morning.4.我们应该在扔掉废物前进行分类。We should divide the waste into different groups before ______ it ______.5.有人担心将来机器人会取代人类。Some people worry that robots will take the place of humans ______ the ______. 1. Did have 2. until / before leave 3. set off /out 4. throwing away /out 5. in future 【解析】 1.原句had是动词have的过去式，需借助did构成一般疑问句，had同时恢复原形。根据句意结构，可知填(1). Did (2). have。 2.原句句意：他们高中毕业后...