2003 年

化學 · 共 33 題 · 點擊選項即時核對答案

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31.

Which of the following pairs of solution would form a precipitate when they are mixed?

(1)NH₄Cl(aq) and K₂SO₄(aq)

(2)NH₃(aq) and Pb(NO₃)₂(aq)

(3)(NH₄)₂CO₃(aq) and CaCl₂(aq)

32.

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
Polyethene is used for making the handle of frying pans.	The shape of the polyethene handle remains unchanged during the frying process.

33.

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
Sodium carbonate can be used to soften hard water which contains calcium ions.	Sodium carbonate reacts with calcium ions in hard water to form a precipitate.