1.简单
What is a horizontal row of the periodic table called?
- AA family
- BA group
- CA period
- DA block
2.简单
Which acid is found in the stomach?
- ANitric acid
- BHydrochloric acid
- CSulfuric acid
- DAcetic acid
3.简单
化学中的摩尔是什么?
- A一升任何气体的体积
- B含有 6.02 × 10²³ 个粒子的物质的量
- C原子中的质子数
- D按标度恰好一个碳-12 原子的克数质量
4.中等
What percentage of the mass of water (H₂O, 18 g/mol) is hydrogen (H = 1 g/mol)?
- AAbout 5.6%
- BAbout 67%
- CAbout 11%
- DAbout 89%
5.中等
Rubbing alcohol evaporates faster than water at room temperature. What does this suggest?
- AIts intermolecular forces are weaker than water's
- BIt has a higher boiling point than water
- CIts molecules are heavier than water molecules
- DIts intermolecular forces are stronger than water's
6.中等
What is the formula of the hydroxide ion?
- AH₃O⁺
- BOH⁺
- CO²⁻
- DOH⁻
7.困难
In the Bohr model, what happens when an electron drops from a higher energy level to a lower one?
- AThe atom gains a proton
- BEnergy is released, often as light
- CThe electron leaves the atom
- DEnergy is absorbed from the surroundings
8.困难
A solution of acetic acid conducts electricity only weakly, while hydrochloric acid of the same concentration conducts strongly. Why?
- AHydrochloric acid contains metal atoms
- BAcetic acid only partly ionises, so it forms fewer ions
- CAcetic acid forms more ions than hydrochloric acid does
- DAcetic acid does not dissolve in water at all
答案
- 1. C · A period
- 2. B · Hydrochloric acid
- 3. B · 含有 6.02 × 10²³ 个粒子的物质的量
- 4. C · About 11%
- 5. A · Its intermolecular forces are weaker than water's
- 6. D · OH⁻
- 7. B · Energy is released, often as light
- 8. B · Acetic acid only partly ionises, so it forms fewer ions
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