Question
Which statements about lime are correct?
1 Lime is made by heating calcium carbonate (limestone).
2 Lime is used to desulfurise flue gases.
3 Lime is used to treat alkaline soil.
4 The chemical name for lime is calcium oxide.
A. 1 and 3 B. 1, 2 and 4 C. 1 and 4 only D. 2, 3 and 4
Answer/Explanation
Ans:
B
Question
When aqueous sodium hydroxide is added to a solution of a metal ion, a grey-green precipitate
forms, which dissolves in excess to form a dark green solution.
What is the identity of the metal ion?
A chromium(III)
B iron(II)
C iron(III)
D copper(II)
Answer/Explanation
Ans: A
Question
Sodium nitrate is a white crystalline solid that decomposes on heating.
Which row describes the decomposition products formed when sodium nitrate is heated strongly?
▶️Answer/Explanation
Ans:B
Question
The equation for a reaction occurring in the Contact process is shown.
\(2SO_{2}+O_{2}\rightarrow 2SO_{3}\)
What is the catalyst used in this reaction?
A. iron
B. phosphoric(V) acid
C. sulfuric acid
D. vanadium(V) oxide
Answer/Explanation
Ans:
D