题目

_______ in the queue for half an hour, Tom suddenly realized that he had left his wallet at home. A . To wait B . Have waited C . Having waited D . To have waited 答案：C（2011?盐城模拟）类推是化学学习中常用的思维方法．下列类推结果不正确的是（ ）A．CaCO3能与稀盐酸反应生成CO2，碳酸盐都能与稀盐酸反应生成CO2B．H2点燃前需验纯，可燃性气体点燃前都需验纯C．NaOH能使无色酚酞溶液变红色，碱都能使无色酚酞溶液变红色D．硝酸铵溶于水会使溶液温度降低，能使溶液温度降低的物质不一定是硝酸铵