1.简单
What is a beta particle?
- AA high-energy electron released from a nucleus
- BA wave of visible light
- CA neutron that leaves the nucleus
- DA helium nucleus with two protons and two neutrons
2.简单
What is the formula of sulfuric acid?
- AH₂SO₃
- BH₂SO₄
- CHNO₃
- DHCl
3.简单
下列哪一项是物理变化?
- A牛奶变酸
- B面包烤成褐色
- C水沸腾变成水蒸气
- D铁生锈
4.中等
下列哪项描述的是吸热过程?
- A它吸收热量,所以周围环境感觉更冷
- B它只在非常高的温度下发生
- C它释放热量,所以周围环境感觉更暖
- D它既不吸收也不释放任何能量
5.中等
In a closed container, 10 g of substance A reacts completely with 5 g of substance B. What is the total mass of the products?
- A15 g
- B5 g
- C10 g
- D50 g
6.中等
温度恒定时,气体的体积减半。其压强会怎样?
- A减半
- B加倍
- C不变
- D变为原来的四分之一
7.困难
Why is Dmitri Mendeleev's early periodic table regarded as such a success?
- AHe arranged the elements by atomic number, which he had discovered
- BHe proved that the atoms of every element contain electrons
- CHe left gaps and correctly predicted the properties of elements not yet discovered
- DHe discovered the noble gases and placed them in group 18
8.困难
What is the net ionic equation for the neutralisation of any strong acid by any strong base?
- ANa⁺ + Cl⁻ → NaCl
- BH⁺ + OH⁻ → H₂O
- CH⁺ + Cl⁻ → HCl
- DH₂ + O₂ → H₂O₂
答案
- 1. A · A high-energy electron released from a nucleus
- 2. B · H₂SO₄
- 3. C · 水沸腾变成水蒸气
- 4. A · 它吸收热量,所以周围环境感觉更冷
- 5. A · 15 g
- 6. B · 加倍
- 7. C · He left gaps and correctly predicted the properties of elements not yet discovered
- 8. B · H⁺ + OH⁻ → H₂O
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