Best reductant reduces chloroform to:

Options

A. `C_(2)H_(4)`
B. `CH_(4)`
C. `C_(2)H_(2)`
D. `C_(2)H_(6)`

Answer

To solve the problem of identifying the best reductant that reduces chloroform (CHCl3) to a hydrocarbon, we need to analyze the oxidation states of carbon in the given options. Here's a step-by-step solution:

### Step 1: Determine the oxidation state of carbon in chloroform (CHCl3).
- The formula for calculating the oxidation state of carbon (C) in CHCl3 is:
\[ \text{Oxidation state of C} = x + 1 \cdot (-1) + 3 \cdot (-1) = 0 \]
- This simplifies to:
\[ x - 3 = 0 \implies x = +3 \]
- Thus, the oxidation state of carbon in chloroform (CHCl3) is +3.

### Step 2: Calculate the oxidation state of carbon in each of the options.
1. **C2H4 (Ethylene)**
- Let the oxidation state of carbon be \( x \):
\[ 2x + 4 \cdot (-1) = 0 \implies 2x - 4 = 0 \implies 2x = 4 \implies x = +2 \]

2. **CH4 (Methane)**
- Let the oxidation state of carbon be \( x \):
\[ x + 4 \cdot (-1) = 0 \implies x - 4 = 0 \implies x = -4 \]

3. **C2H2 (Acetylene)**
- Let the oxidation state of carbon be \( x \):
\[ 2x + 2 \cdot (-1) = 0 \implies 2x - 2 = 0 \implies 2x = 2 \implies x = +1 \]

4. **C2H6 (Ethane)**
- Let the oxidation state of carbon be \( x \):
\[ 2x + 6 \cdot (-1) = 0 \implies 2x - 6 = 0 \implies 2x = 6 \implies x = +3 \]

### Step 3: Compare the oxidation states.
- The calculated oxidation states are:
- C2H4: +2
- CH4: -4
- C2H2: +1
- C2H6: +3

### Step 4: Identify the best reductant.
- The best reductant is the one that can reduce chloroform to the lowest oxidation state.
- Among the options, CH4 has the lowest oxidation state of -4.

### Conclusion:
The best reductant that reduces chloroform (CHCl3) to a hydrocarbon is **CH4 (Methane)**.

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