题干
—I am going to visit New York for a month.
—Great! It's a good _______ to practice English.
—Great! It's a good _______ to practice English.
A：chance
B：habit
C：skill
D：exercise
答案(点此获取答案解析）
A
nC(g)+2D(g) 达到平衡后，A物质的量浓度减小1/2，混合气体的平均摩尔质量增大1/8，则该反应的化学方程式中n的值是（ )