血吸虫成虫平均寿命为()
A.1~6个月
B.6~12个月
C.1~2年
D.2~3年
E.4~5年
参考答案:E
实验室里常用浓盐酸与二氧化锰反应来制取少量的氯气,反应的化学方程式为MnO2+4HCl═MnCl2+Cl2↑+2H2O,欲制得标准状况下4.48L氯气,
(1)参与反应的HCl的物质的量是多少?
(2)反应中实际被氧化的HCl的物质的量是多少?
—Look! The telephone is broken. Someone damaged it purpose.
—That may be right. But perhaps it was broken accident. [ ]
A. on; by
B. by; by
C. on; on
D. by; on