2008 年

化學 · 共 45 題 · 點擊選項即時核對答案

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41.

A certain form of solid carbon is composed of C₆₀ molecules. Each C₆₀ molecule is formed by 60 carbon atoms bonded together like a football as shown in the diagram below:

Which of the following statements is/are correct ?

(1)The molar mass of C₆₀ is 12.0 g.

(2)The solid gives carbon dioxide upon complete combustion.

(3)The melting point of the solid is higher than that of diamond.

42.

The empirical formula of an organic compound T is CH₂O. Effervescence occurs when T is added to sodium carbonate solution. T may be

(1)HCOOCH₃.

(2)CH₃CH(OH)COOH.

(3)CH₃CH₂CH₂COOH.

43.

Upon electrolysis, which of the following solutions would give hydrogen at carbon cathode and oxygen at platinum anode ?

(1)very dilute sodium chloride solution

(2)dilute copper(II) sulphate solution

(3)concentrated potassium sulphate solution

44.

For each of the following questions, decide whether each of the two statements is true or false. If both are true, decide whether the second correctly explains the first.

A.Both statements are true and the 2nd statement is a correct explanation of the 1st statement.

B.Both statements are true but the 2nd statement is NOT a correct explanation of the 1st statement.

C.The 1st statement is false but the 2nd statement is true.

D.Both statements are false.

1st statement	2nd statement
Fractional distillation can convert large alkane molecules to smaller alkane molecules and alkene molecules.	Fractional distillation involves breaking and forming of covalent bonds.

45.

For each of the following questions, decide whether each of the two statements is true or false. If both are true, decide whether the second correctly explains the first.

A.Both statements are true and the 2nd statement is a correct explanation of the 1st statement.

B.Both statements are true but the 2nd statement is NOT a correct explanation of the 1st statement.

C.The 1st statement is false but the 2nd statement is true.

D.Both statements are false.

1st statement	2nd statement
When equal mass of Mg and Zn granules is added separately to excess dilute H₂SO₄, a greater amount of gas will be produced by Mg than Zn.	Mg is more reactive than Zn.