2003 年
化學 · 共 33 題 · 點擊選項即時核對答案
Which of the following pairs of elements in Group I and VII of the Periodic Table would react with each other most vigorously ?
| Group I | Group VII | |
|---|---|---|
| lithium | fluorine | |
| lithium | iodine | |
| potassium | fluorine | |
| potassium | iodine |
Which of the following substances, upon heating in a test tube, would undergo a chemical change ?
When a small piece of calcium metal is put into a trough of water, a reaction occurs. Which of the following statements concerning this reaction is correct ?
Which of the following statements concerning nitric acid is INCORRECT?
Which of the following methods can be used to obtain aluminium from aluminium oxide ?
Sodium azide, NaN₃, is used in air bags in cars. When there is a serious collision, the azide will decompose to give nitrogen. The decomposition can be represented by the equation: 2NaN₃(s) → 2Na(s) + 3N₂(g) What is the mass of sodium azide required to produce 72 dm³ of nitrogen at room temperature and pressure? (Relative atomic masses: N = 14.0, Na = 23.0; molar volume of gas at room temperature and pressure = 24 dm³)
Which of the following statements concerning halogens is INCORRECT ?
Which of the following combinations is correct?
| Homologous series | General formula | |
|---|---|---|
| alkanes | CₙH₂ₙ | |
| alkenes | CₙH₂ₙ₊₂ | |
| alkanols | CₙH₂ₙOH | |
| alkanoic acids | CₙH₂ₙ₊₁CO₂H |
Which of the following combinations is correct?
| Chemical | Hazardous nature | |
|---|---|---|
| sodium | oxidizing | |
| mercury | toxic | |
| ethyl ethanoate | irritant | |
| potassium dichromate | explosive |
A sample of MgSO₄ • xH₂O(s) of mass 123.2 g contains 63.0 g of water of crystallization. What is the value of x ? (Relative atomic masses: H = 1.0, O = 16.0, Mg = 24.3, S = 32.1)