护理入学考试化学练习卷（附答案）

In a solution, what is the solvent?

1. AThe substance that is dissolved, usually present in the smaller amount
2. BAny solid that will not dissolve, however long it is stirred
3. CThe substance that does the dissolving, usually present in the larger amount
4. DThe gas given off when a solid dissolves

Which method separates sand from water?

1. ADistillation
2. BChromatography
3. CEvaporation of the sand
4. DFiltration

在盐溶液中，盐称为什么？

1. A溶剂
2. B溶质
3. C沉淀
4. D催化剂

Which property stays the same whether you have a small sample or a large sample of a pure substance?

1. ADensity
2. BTotal heat content
3. CVolume
4. DMass

Why do group 1 metals such as sodium react so easily?

1. AThey have a full outer shell of electrons
2. BTheir nuclei contain no neutrons
3. CThey have one outer electron that is easily lost
4. DThey easily gain one extra electron

Which equation shows a combustion reaction?

1. ACaCO₃ → CaO + CO₂
2. BC₂H₅OH + 3O₂ → 2CO₂ + 3H₂O
3. CNaOH + HCl → NaCl + H₂O
4. DZn + CuSO₄ → ZnSO₄ + Cu

Frying an egg turns the clear egg white solid and white. What happens to the proteins?

1. AThey are denatured: their shape changes, but the peptide bonds stay intact
2. BThey are burned to carbon dioxide and water
3. CThey are hydrolysed, so the peptide bonds break into separate amino acids
4. DThey are converted into fats

At the top of a high mountain, air still contains about 21% oxygen. Why do climbers still get less oxygen with each breath?

1. AThe total air pressure is lower, so the partial pressure of oxygen is lower
2. BOxygen is heavier, so it all sinks to sea level
3. CThe percentage of oxygen in the air falls sharply as you climb higher
4. DCold air contains no oxygen