题干
— _____ Sam ______ a soccer ball?
— No, she doesn't. But his brother does.
A：Do; has
B：Does; have
C：Do; have
D：Does; has
答案(点此获取答案解析）
B
CO2(g)＋H2(g)，反应达到平衡后，测得CO2的物质的量为0.6 mol。然后再充入4 mol H2O(g)，达到新的平衡后，CO2的物质的量为( )