Question

10 Given the balanced ionic equation representing a reaction:

Zn(s) + Co2+(aq) → Zn2+(aq) + Co(s)
Which statement describes the electrons involved in this
reaction?
A) Each Zn atom loses 2 electrons, and each Co2+ ion gains 2
electrons.
B) Each Zn atom loses 2 electrons, and each Co2+ ion loses 2
electrons.
C) Each Zn atom gains 2 electrons, and each Co2+ ion loses 2
electrons.
D) Each Zn atom gains 2 electrons, and each Co2+ ion gains 2
electrons.

Answer 1

Answer: A) Each Zn atom loses 2 electrons, and each Co2+ ion gains 2 electrons.

Answer 2

Option (A) Each Zn atom loses 2 electrons, and each Co2+ ion gains 2

Step-by-step explanation:

To know the right answer to the question, let us observe the changes in the oxidation number of Zn and Co. This is illustrated below:

Zn(s) + Co2+(aq) → Zn2+(aq) + Co(s)

The oxidation number of Zn changes from 0 to +2 indicating that Zn has lose 2 electrons.

The oxidation number of Co changes from +2 to 0 indicating that Co has gain 2 electrons.

Therefore, option A is the correct answer.