化學 1995 年 DSE、CE 選擇題（第 4 頁）

31.

Astatine is a Group VII element below iodine in the Periodic Table. Which of the following statements concerning astatine is / are correct?

(1)It is a liquid at room temperature and pressure.

(2)It reacts with sodium to form an ionic compound.

(3)It is a stronger oxidising agent than iodine.

32.

Which of the following statements concerning a silver oxide cell is / are correct?

(1)The cell is rechargeable.

(2)The cell can maintain a steady voltage during discharge.

(3)The positive electrode of the cell is silver oxide.

33.

Which of the following particles is / are present in a hydrogen ion?

(1)proton.

(2)neutron.

(3)electron.

34.

Which of the following substances, when mixed with lemon juice, would give off gas bubbles?

(1)iron nails.

(2)milk of magnesia.

(3)polyethene wrap.

35.

Which of the following statements concerning urea-methanal is / are correct?

(1)It softens on gentle heating.

(2)It can be used to make ash trays.

(3)It consists of polymer chains with cross-linkages between the chains.

36.

In the set-up shown, metal X is more reactive than metal Y.

Which of the following statements concerning this set-up is / are correct?

(1)Electrolysis occurs inside the lemon.

(2)Chemical energy is changed into electrical energy.

(3)Electrons flow from metal Y to metal X in the external circuit.

37.

Which of the following statements concerning the Contact Process is / are correct?

(1)The sulphur dioxide used in the process can be produced by roasting sulphide ores.

(2)A gaseous mixture of sulphur dioxide and oxygen in the mole ratio of 1 : 2 is passed into the catalytic conversion chamber.

(3)The sulphur trioxide produced is absorbed by water in the absorption tower.

38.

Which of the following substances can conduct electricity?

(1)molten zinc chloride.

(2)an aqueous solution of magnesium sulphate.

(3)a mixture of ethanol and water.

39.

Which of the following methods can produce hydrogen?

(1)adding zinc to water.

(2)electrolysing dilute sulphuric acid.

(3)adding magnesium to dilute hydrochloric acid.

40.

Which of the following statements concerning the recycling of plastics are correct?

(1)The recycling of plastics can help to solve the disposal problem of plastics.

(2)The recycling of plastics can save raw materials derived from petroleum.

(3)It is difficult to separate different types of plastics in the recycling process.