Which of the following gases is normally not present in air?A.Oxygen B.HydrogenC.Nitrogen D.Carbon DioxideWaiting online!QUICK!Thanks Guys!To myth2000:Sorry but one answer is too little for me..lets w
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BNormally,the air is bined by 20.25% Oxygen(A),78% Nitrogen (B),0.03% Carbon Dioxide (D) and some other rare gases.Anyway Hydrogen (B) is also one of the ponents of air,but the content is very v...
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供参考答案1:
B 氢气