1、单选题：
The unit operation of separation of gas mixture based on the difference of components’solubility is . 利用气体各组分在液体中的溶解度的不同而实现气体分离的单元操作是。（ ）
选项：
A:Absorption吸收
B:Adsorption吸附
C:Extraction萃取
D:Distillation 精馏
答案: 【Absorption吸收】

2、单选题：
Please judge which following unit operation belongs to mass transfer? 请判断哪个单元操作属于质量传递? ( )
选项：
A:Heating 加热
B:Settling 沉降
C:Filtration 过滤
D:Distillation 精馏
答案: 【Distillation 精馏】

3、单选题：
Which unit operation belongs to heat transfer? 哪个单元操作属于热量传递?( )
选项：
A:Stirring 搅拌
B:Transportation of fluids 流体输送
C:Settling 沉降
D:Cooling 冷却
答案: 【Cooling 冷却】

4、单选题：
As we all know, "three transfers" is a very important concept, which includes momentum, heat, and mass transfer, now judge which following unit operation belongs to momentum transfer? 总所周知，三传是非常重要的概念，它包括动量、热量和质量传递，请判断哪个单元操作属于动量传递?( )
选项：
A:Absorption吸收
B:Cooling 冷却
C:Transportation of fluids 流体输送
D:Distillation精馏
答案: 【Transportation of fluids 流体输送】

5、单选题：
Some unit operations just include 1 transfer, however others maybe include 2 or 3 transfers at the same time, please indicate the unit operation below that exists mass and heat transfers meanwhile?一些单元操作只存在一种传递，有些则同时存在2到3种单元操作，请指出下面哪个单元操作既属于质量传递同时也属于热量传递？( )
选项：
A:Cooling 冷却
B:Transportation of fluids 流体输送
C:Heating加热
D:Distillation精馏
答案: 【Distillation精馏】