F.4 Chem MC Need Reason!!!

Question

X and Y are two different metals. Which of the followings shows that Y is more reactive than X?

A. X forms an ion with a charge of +2 while Y forms an ion with a charge of +1

B. X reacts with dilute hydrochloric acid but Y does not.

C. X can displace Y form an aqueous solution of a salt of Y.

D. The oxide of X undergoes decomposition upon strong heating but the oxide of Y does not.

Answer 1

最愛解答

Option A: It is only true when elements X and Y are in the same period, e.g. in Period 4, K is more reactive than Ca.

Option B: If so, then it's X more reactive than Y.

Option C: Again, it shows that X is more reactive than Y, as a more reactive metal ( M1 ) displays a less reactive metal ( M2 ) in M2's aqueous solution.

Option D: Correct. It shows that X forms a less stable ore and extraction of it from its ore is easier, as only directly heating is required.

Ans: D

資料來源： My Chem Knowledge