2000 年
化學 · 共 34 題 · 點擊選項即時核對答案
A compound formed from element X and sulphur has the following electronic structure:
(Only electrons in the outermost shells are shown.) How many electrons are there in the outermost shell of an atom of X ?
Metal X forms an oxide. 27.53 g of this oxide contains 24.96 g of X. What is the mole ratio of X to oxygen in the oxide ? (Relative atomic masses: O = 16.0, X = 207.0)
Which of the following gases are the major products liberated in the electrolysis of concentrated sodium chloride solution using carbon electrodes ?
| Cathode | Anode | |
|---|---|---|
| hydrogen | chlorine | |
| chlorine | hydrogen | |
| hydrogen | oxygen | |
| oxygen | hydrogen |
Which of the following pairs of compounds can be distinguished by treating with an acidified potassium dichromate solution?
Element X occurs in nature as two isotopes, ⁶³X and ⁶⁵X. If the relative atomic mass of X is 63.5, what is the relative abundance of the ⁶³X isotope ?
Which of the following statements concerning members of a homologous series is INCORRECT?
The atomic number of element X is 12. X reacts with element Y to form an ionic compound with formula XY₂. To which group of the Periodic Table does Y belong ?
Different volumes of 2.0 M potassium hydroxide solution and 2.0 M sulphuric acid are mixed in a polystyrene cup. In which of the following combination would the temperature rise be the greatest?
| Volume of 2.0 M KOH(aq) / cm³ | Volume of 2.0 M H₂SO₄(aq) / cm³ | |
|---|---|---|
| 20.0 | 40.0 | |
| 30.0 | 30.0 | |
| 40.0 | 20.0 | |
| 45.0 | 15.0 |
Consider the compounds represented by the two structures below:
Which of the following statements concerning these compounds is correct ?
Which of the following solutions can react with bromine water to give a colourless solution?