Question

Given the two half-reactions, what must be done in the next step before the reaction can be balanced?

Au³⁺ → Au
I⁻ → I₂ .

(A) Determine the number of electrons transferred between the two half-reactions.
(B) Determine the oxidation states of the atoms involved in each half-reaction.
(C) Multiply each half-reaction by a coefficient so that the total number of electrons transferred is the same in both half-reactions.
(D) Determine the products of the reaction.

Answer 1

Before balancing the reaction, the number of electrons transferred in both half-reactions must be equalized by multiplying each half-reaction by an appropriate coefficient. The correct answer is option: C. Multiply each half-reaction by a coefficient so that the total number of electrons transferred is the same in both half-reactions.

Step-by-step explanation:

The next step before the reaction can be balanced is to multiply each half-reaction by a coefficient so that the total number of electrons transferred is the same in both half-reactions.

This step ensures the mass conservation and the principle that redox reactions involve the transfer of electrons, which is a key aspect of balancing redox reactions.

For example, if one half-reaction involves the loss of two electrons and the other the gain of six electrons, the first half-reaction must be multiplied by three to equalize the number of electrons with the second half-reaction.

The correct answer is option: C. Multiply each half-reaction by a coefficient so that the total number of electrons transferred is the same in both half-reactions.