1.简单
What is oxidation, in terms of electrons?
- ALoss of electrons
- BGain of neutrons
- CGain of electrons
- DLoss of protons
2.简单
钠和钾属于哪一族?
- A碱土金属(第 2 族)
- B卤素(第 17 族)
- C稀有气体(第 18 族)
- D碱金属(第 1 族)
3.简单
Which gas is needed for a fuel to burn (combustion)?
- ANitrogen
- BCarbon dioxide
- COxygen
- DHelium
4.中等
What is the formula of sodium sulfate, made from Na⁺ and SO₄²⁻ ions?
- ANaSO₄
- BNa₄SO₂
- CNa(SO₄)₂
- DNa₂SO₄
5.中等
During digestion, large molecules are broken down by adding water across their bonds. What is this reaction called?
- AHydrolysis
- BPolymerisation
- CCombustion
- DCondensation
6.中等
Why can a very high fever disrupt the body's chemical reactions?
- AHigh temperatures can change the shape of enzymes so they stop working
- BHigh temperatures make every enzyme work faster without any limit
- CHigh temperatures turn enzymes into fats
- DHigh temperatures remove the water from blood
7.困难
一种金属与酸反应,放出一种气体,燃烧时发出"噗"的爆鸣声。这是哪种气体?
- A氢气
- B氮气
- C二氧化碳
- D氧气
8.困难
Why does a sodium ion (Na⁺) have almost the same mass as a sodium atom?
- AThe only difference is one electron, which has a tiny mass
- BIons and atoms always have exactly the same mass
- CThe ion gains a neutron that balances the loss
- DThe ion has one fewer proton, which has a tiny mass
答案
- 1. A · Loss of electrons
- 2. D · 碱金属(第 1 族)
- 3. C · Oxygen
- 4. D · Na₂SO₄
- 5. A · Hydrolysis
- 6. A · High temperatures can change the shape of enzymes so they stop working
- 7. A · 氢气
- 8. A · The only difference is one electron, which has a tiny mass
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