Question

What is the balanced reaction for the cell diagram below?

a. \(3\text{Cd}^{2+} + 2\text{Al} \rightarrow 3\text{Cd} + 2\text{Al}^{3+}\)

b. \(2\text{Al} + 3\text{Cd}^{2+} \rightarrow 2\text{Al}^{3+} + 3\text{Cd}\)

c. \(2\text{Al}^{3+} + 3\text{Cd} \rightarrow 2\text{Al} + 3\text{Cd}^{2+}\)

d. \(3\text{Cd} + 2\text{Al}^{3+} \rightarrow 3\text{Cd}^{2+} + 2\text{Al}\)

Answer 1

The balanced reaction for Al and Cd in a cell diagram is '2Al + 3Cd^2+ → 2Al^3+ + 3Cd', which is option (b) in the question provided.

Step-by-step explanation:

The balanced reaction for the cell diagram mentioned would show the relationship between the oxidation and reduction processes involving specific elements. In a balanced chemical equation, both the number of atoms for each element and the total charge must be the same on both sides of the equation.

As an example, the half-reaction for aluminum becoming an aluminum ion is:

• Al → Al3+ + 3e−

And for cadmium ion becoming a cadmium atom is:

• Cd2+ + 2e− → Cd

To balance the number of electrons transferred, the cadmium half-reaction should occur thrice, and the aluminum half-reaction should occur once:

• 3Cd2+ + 6e− → 3Cd
• 2Al + 6e− → 2Al3+

The balanced chemical equation becomes:

2Al + 3Cd2+ → 2Al3+ + 3Cd

This corresponds to option (b) in the original problem set.