某固态非金属单质A和氧气发生化合反应生成B（B为气体），在同温同压的条件下，气体B的体积是反应掉氧气体积的两倍．以下对B的分子组成的推测一定正确的是（ ）
A．有1个氧原子
B．有2个氧原子
C．有1个A原子
D．有2个A原子
同温同压下气体的Vm相同，由n=
可知，气体的体积之比等于物质的量之比，则有1molO2可生成2molB，V Vm
则B中应含有1个O，
故选A．
| Choose the correct questions for the answers. 为下列答语选择正确的问句。 |
| ( )1. Yes, I would like to. ( )2. I want that one over there. ( )3. It's twenty dollars. ( )4. Bob's team won the basketball game. ( )5. I went to the park today. | A. Yes, I would like to. B. Wherte did you go today? C. How much is the basketball? D. Would you like to watch games? E. Who went to the park today. |