问题
选择题
To the teacher's surprise, the boy had no ____ out the ____ maths problem. [ ]
A. difficulty to work; difficult
B. difficult working; difficulty
C. difficulty working; difficult
D. difficulty in working; difficulty
答案
答案：C
2NH3并达到平衡，此时向平衡混合物中再次充入3 mol N2和3 mol H2，重新达到平衡后N2、H2的转化率将：N2 ，H2 。（填“增大”、“减小”、“不变”或“不能确定”）