Four `Cl_(2)` molecules undergo a loss and gain of `6 "mole" ` of electrons to form two oxidation states of `Cl` in a auto redox change. What are the `+ve` and `-ve` oxidation state of `Cl` in the change?

Options

A. `Cl^(5+),Cl^(@)`
B. `Cl^(7+),Cl^(-)`
C. `Cl^(3+),Cl^(@)`
D. `Cl^(3),Cl^(-)`

Answer

To find the positive and negative oxidation states of chlorine (Cl) in the given auto-redox change involving four Cl₂ molecules, we can follow these steps:

### Step 1: Identify the oxidation state of Cl in Cl₂
In its elemental form (Cl₂), chlorine has an oxidation state of 0.

### Step 2: Understand the concept of auto-redox reaction
An auto-redox reaction involves the same element being both oxidized and reduced. In this case, chlorine is undergoing both processes.

### Step 3: Determine the total number of moles of electrons involved
The problem states that there is a loss and gain of 6 moles of electrons. This means that some chlorine atoms are being oxidized (losing electrons) while others are being reduced (gaining electrons).

### Step 4: Assign oxidation states for the products
- When chlorine gains electrons, it is reduced. The common oxidation state for reduced chlorine is -1 (Cl⁻).
- When chlorine loses electrons, it is oxidized. The common oxidation state for oxidized chlorine is +3 (Cl⁺).

### Step 5: Write the half-reactions
1. **Reduction half-reaction**:
\[ Cl_2 + 6e^- \rightarrow 2Cl^- \]
Here, chlorine goes from 0 to -1 oxidation state.

2. **Oxidation half-reaction**:
\[ 2Cl^+ \rightarrow Cl_2 + 6e^- \]
Here, chlorine goes from 0 to +3 oxidation state.

### Step 6: Balance the overall reaction
Since we have 4 moles of Cl₂, we can combine the half-reactions to ensure that the total number of electrons lost equals the total number of electrons gained.

### Step 7: Conclusion
The two oxidation states of chlorine formed in this auto-redox reaction are:
- Negative oxidation state: -1 (Cl⁻)
- Positive oxidation state: +3 (Cl⁺)

Thus, the answer is that the oxidation states of Cl in the change are -1 and +3.