In the redox reaction Zn + Cu^{2+} → Zn^{2+} + Cu, which species is oxidized?

• A. Zn
• B. Cu^{2+}
• C. Cu
• D. Zn^{2+}

Answer: (A)

Verified step by step guidance

1. Identify the oxidation states of each species before and after the reaction. Zinc (Zn) starts as a neutral atom with an oxidation state of 0, and copper ion (Cu^{2+}) starts with an oxidation state of +2.
2. Determine the oxidation states of the products. Zinc ion (Zn^{2+}) has an oxidation state of +2, and copper (Cu) is a neutral atom with an oxidation state of 0.
3. Recall that oxidation is the loss of electrons, which corresponds to an increase in oxidation state, while reduction is the gain of electrons, corresponding to a decrease in oxidation state.
4. Compare the changes in oxidation states: Zn goes from 0 to +2 (oxidation), and Cu^{2+} goes from +2 to 0 (reduction).
5. Conclude that the species that is oxidized is the one whose oxidation state increases, which in this case is Zn.