1.简单
What is the formula of sulfuric acid?
- AH₂SO₃
- BHCl
- CH₂SO₄
- DHNO₃
2.简单
下列哪一项是化合物?
- A铁(Fe)
- B二氧化碳(CO₂)
- C氧气(O₂)
- D氦(He)
3.简单
什么是放热反应?
- A需要光才能开始的反应
- B从周围环境吸收热量的反应
- C完全没有能量变化的反应
- D向周围环境释放热量的反应
4.中等
Uranium-235 and uranium-238 both have 92 protons. How many more neutrons does an atom of uranium-238 have?
- A92
- B0
- C3
- D146
5.中等
Water climbs up a narrow glass tube. Which property mainly causes this?
- AWater's high boiling point
- BLow density of water
- CAdhesion of water to the glass
- DEvaporation of water from the tube
6.中等
哪种改变会使一块粉笔与酸反应得更快?
- A把粉笔研磨成粉末
- B用更多水稀释酸
- C把酸放进冰箱冷却
- D使用一大块粉笔
7.困难
Element A has 1 valence electron and element B has 7 valence electrons, both in period 3. Which statement best compares them?
- ABoth are unreactive because they are in the same period
- BBoth are metalloids
- CA is a reactive metal and B is a reactive nonmetal
- DA is a nonmetal and B is a metal
8.困难
在 2H₂ + O₂ → 2H₂O 中,4 g 氢气(摩尔质量 2 g/mol)与足量氧气反应。生成多少质量的水(摩尔质量 18 g/mol)?
- A18 g
- B72 g
- C4 g
- D36 g
答案
- 1. C · H₂SO₄
- 2. B · 二氧化碳(CO₂)
- 3. D · 向周围环境释放热量的反应
- 4. C · 3
- 5. C · Adhesion of water to the glass
- 6. A · 把粉笔研磨成粉末
- 7. C · A is a reactive metal and B is a reactive nonmetal
- 8. D · 36 g
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