Question

Using the following portion of the activity series for oxidation half-reactions, determine which combination of reactants will result in a reaction.

Na(s) → Na⁺(aq) + e⁻
Cr(s) → Cr³⁺(aq) + 3e⁻


A) Na⁺(aq) with Cr(s)
B) Na⁺(aq) with Cr³⁺(aq)
C) Na(s) with Cr(s)
D) Na(s) with Cr³⁺(aq)

Answer 1

The combination of Na⁺(aq) with Cr³⁺(aq) will result in a reaction.

Step-by-step explanation:

The given activity series for oxidation half-reactions can be used to determine which combination of reactants will result in a reaction. In this case, the combination of Na⁺(aq) with Cr³⁺(aq) (option B) will result in a reaction. This is because Na(s) can oxidize and lose an electron to form Na⁺(aq), while Cr³⁺(aq) can be reduced by gaining three electrons to form Cr(s). Therefore, the half-reactions can be combined as:

2Na(s) + 3Cr³⁺(aq) → 2Na⁺(aq) + 3Cr(s)