题目

相同质量的Na、Mg、Al分别与过量的盐酸反应，在相同条件下置换出H2的体积比是      A. 1∶2∶3 B. 23∶12∶9    C. 9∶12∶23   D. 36∶69∶92 答案：D15、The tramp wore large trousers，worn-out shoes and a _________hat． A．black small round                                    B．small round black C．small black round                                       D．round small black