已建立平衡的某可逆反应,当条件改变化学平衡正向移动时,下列叙述正确的是①生成物的体积分数一定增大 ②生成物的产量一定增加 ③生成物的产率一定增大④反应物浓度一定降低 ⑤正反应速率一定大于逆反应速率 ⑥混合气体平均分子量一定增大
She brought with her three friends, none of ______ I had ever met before.
I tried phoning her office, but I couldn’t _______.
His sister left home in 1998, and _______since.
What do you mean, there are only ten tickets? There _____ be twelve
Could I speak to ______ is in charge of International Sales please?