State the oxidation number of carbonyl carbon in methanal and methanoic acid respectively :

Options

A. `0 and 0`
B. `0 and +2`
C. `+1 and +2`
D. `+1 and +3`

Explanation

To determine the oxidation number of the carbonyl carbon in methanal (formaldehyde) and methanoic acid (formic acid), we will follow these steps:

### Step 1: Identify the structure of methanal and methanoic acid
- Methanal (HCHO) has one carbonyl carbon that is double bonded to an oxygen atom.
- Methanoic acid (HCOOH) also has a carbonyl carbon that is double bonded to an oxygen atom, but it has an additional hydroxyl group (-OH).

### Step 2: Calculate the oxidation number of carbonyl carbon in methanal
1. **Write the formula**: The chemical formula for methanal is HCHO.
2. **Assign oxidation states**:
- Hydrogen (H) has an oxidation state of +1.
- Oxygen (O) has an oxidation state of -2.
3. **Set up the equation**: Let the oxidation number of the carbonyl carbon be \( X \).
\[ +1 (from H) + X (from C) - 2 (from O) = 0 \]
4. **Solve the equation**:
\[ 1 + X - 2 = 0 \\ X - 1 = 0 \\ X = +1 \]
5. **Conclusion for methanal**: The oxidation number of the carbonyl carbon in methanal is **0**.

### Step 3: Calculate the oxidation number of carbonyl carbon in methanoic acid
1. **Write the formula**: The chemical formula for methanoic acid is HCOOH.
2. **Assign oxidation states**:
- Hydrogen (H) has an oxidation state of +1.
- Oxygen (O) has an oxidation state of -2.
3. **Set up the equation**: Let the oxidation number of the carbonyl carbon in methanoic acid be \( Y \).
\[ +1 (from H) + Y (from C) + +1 (from another H) - 4 (from 2 O) = 0 \]
4. **Solve the equation**:
\[ 1 + Y + 1 - 4 = 0 \\ Y - 2 = 0 \\ Y = +2 \]
5. **Conclusion for methanoic acid**: The oxidation number of the carbonyl carbon in methanoic acid is **+2**.

### Final Answer
- The oxidation number of the carbonyl carbon in methanal is **0**.
- The oxidation number of the carbonyl carbon in methanoic acid is **+2**.

### Summary
- **Methanal**: Oxidation number of carbonyl carbon = **0**
- **Methanoic acid**: Oxidation number of carbonyl carbon = **+2**