Question

indicate if the process is oxidation, reduction, both, or neither
1 na → e⁻¹ + na⁺¹
2 s + 2 e⁻¹ → s⁻²
3 h - h → 2 h⁰ (molecular hydrogen into hydrogen atoms)
4 2 na + s → na₂s
5 hg → hg⁺² + 2 e⁻¹
6 o + 2 e⁻¹ → o⁻²
7 hg + o → hgo
a. oxidation b. reduction c. oxidation/reduction d. neither

Explanation:

Step1: Recall oxidation - reduction definitions

Oxidation is loss of electrons, reduction is gain of electrons. In a redox reaction, both oxidation and reduction occur simultaneously.

Step2: Analyze reaction 1

Na loses an electron to form Na⁺, so it is oxidation.

Step3: Analyze reaction 2

S gains 2 electrons to form S²⁻, so it is reduction.

Step4: Analyze reaction 3

There is no change in oxidation state of hydrogen, so it is neither oxidation nor reduction.

Step5: Analyze reaction 4

Na loses electrons (oxidation) and S gains electrons (reduction), so it is oxidation/reduction.

Step6: Analyze reaction 5

Hg loses 2 electrons to form Hg²⁺, so it is oxidation.

Step7: Analyze reaction 6

O gains 2 electrons to form O²⁻, so it is reduction.

Step8: Analyze reaction 7

Hg loses electrons (oxidation) and O gains electrons (reduction), so it is oxidation/reduction.

Answer:

1. A. oxidation
2. B. reduction
3. D. neither
4. C. oxidation/reduction
5. A. oxidation
6. B. reduction
7. C. oxidation/reduction