A、5% B.30% C.0.5% D.1.5%
A.無色無味氣體 B.不易溶于水 C.比空氣輕 D.相對分子質(zhì)量是34
A.4.3%~35.5% B.4.3%~45.5% C.35.5%~70% D.15.7%~27.4%