护理入学考试化学练习卷（附答案）

What are the usual units of molar mass?

1. Amol/L
2. Bg/L
3. Cg/mol
4. Dmol/g

水的化学式是什么？

1. AOH
2. BHO₂
3. CH₂O₂
4. DH₂O

In a chemical equation, what are the reactants?

1. AThe catalysts written above the arrow
2. BThe new substances formed, written to the right of the arrow
3. CThe numbers written in front of each formula
4. DThe starting substances, written to the left of the arrow

在刚性密闭容器中加热气体时，其压强会怎样？

1. A增大
2. B降为零
3. C不变
4. D减小

Why does water boil at a lower temperature at the top of a high mountain?

1. AThe air pressure is lower, so less vapour pressure is needed to boil
2. BGravity is weaker, so the molecules escape more easily
3. CThere is less oxygen dissolved in the water up there
4. DThe air is colder, so the water loses heat and boils sooner

Which halogen is the most reactive?

1. AChlorine
2. BBromine
3. CFluorine
4. DIodine

A reaction at equilibrium has a very large equilibrium constant (K much greater than 1). What does this tell you?

1. AAt equilibrium, the mixture contains mostly reactants
2. BAt equilibrium, the mixture contains mostly products
3. CThe reaction is very fast
4. DThe reaction cannot reach equilibrium

Pepsin digests protein in the stomach at about pH 2, but it stops working once food moves into the small intestine, where the pH is higher. Why?

1. APepsin only works on fats in the small intestine
2. BThe small intestine is too cold for any enzyme
3. CThe change in pH alters the shape of pepsin's active site
4. DPepsin is used up completely in the stomach, just like a reactant