1999 年
化學 · 共 50 題 · 點擊選項即時核對答案
Consider the following chemical equation : 2HNO₃ + xFeSO₄ + yH₂SO₄ → zFe₂(SO₄)₃ + 4H₂O + 2NO Which of the following combinations is correct ?
| x | y | z | |
|---|---|---|---|
| 2 | 1 | 1 | |
| 4 | 3 | 2 | |
| 6 | 2 | 3 | |
| 6 | 3 | 3 |
In which of the following situations is iron prevented from rusting by sacrificial protection ?
Which of the following combinations is correct ?
| Food additive | Function | |
|---|---|---|
| sodium benzoate | flavour enhancement | |
| sugar | dehydration | |
| monosodium glutamate | sweetening | |
| vinegar | antioxidizing |
In an experiment, sulphur dioxide is passed into an iodine solution which is prepared by dissolving some iodine in potassium iodide solution. Which of the following statements concerning this experiment is correct ?
In an experiment, 1.00 M sodium hydroxide solution was added to 25.0 cm³ of 1.00 M sulphuric acid until the acid was completely neutralized. What is the concentration of sodium sulphate (correct to two decimal places) in the resulting solution ?
Questions 26 and 27 refer to the following experiment : Some concentrated sulphuric acid and pumice stones were added to an alkanol and an alkanoic acid. The mixture was heated under reflux for some time and the following compound was obtained :
Which of the following combinations is correct ?
| Alkanol | Alkanoic acid | |
|---|---|---|
| methanol | ethanoic acid | |
| methanol | propanoic acid | |
| ethanol | ethanoic acid | |
| ethanol | propanoic acid |
Questions 26 and 27 refer to the following experiment : Some concentrated sulphuric acid and pumice stones were added to an alkanol and an alkanoic acid. The mixture was heated under reflux for some time and the following compound was obtained :
Which of the following statements concerning the experiment is correct ?
Which of the following substances is a thermoplastic as well as a condensation polymer ?
Which of the following statements concerning household bleach is correct ?
Which of the following combinations is INCORRECT ?
| Pollutant | Harmful effect | |
|---|---|---|
| hydrocarbons | causing liver diseases | |
| carbon monoxide | causing unconsciousness | |
| lead compounds | causing brain damage | |
| carbon particles | causing respiratory diseases |