What is the oxidation number of carbonyl carbon in methanal ?

Options

A. `+3`
B. `+2`
C. `+4`
D. 0

Explanation

To find the oxidation number of the carbonyl carbon in methanal (HCHO), we can follow these steps:

### Step 1: Write the chemical formula of methanal.
Methanal, also known as formaldehyde, has the chemical formula HCHO.

### Step 2: Identify the atoms in the molecule.
In methanal, we have:
- 1 carbonyl carbon (C)
- 1 oxygen (O)
- 2 hydrogen atoms (H)

### Step 3: Assign oxidation numbers to the other atoms.
- The oxidation number of hydrogen (H) is +1.
- The oxidation number of oxygen (O) is -2.

### Step 4: Set up the equation using the X method.
Let the oxidation number of the carbonyl carbon be X. According to the X method, we can set up the equation based on the sum of the oxidation numbers equaling the overall charge of the molecule, which is 0 for methanal.

The equation will be:
\[ X + (2 \times +1) + (-2) = 0 \]

### Step 5: Simplify the equation.
Now, simplify the equation:
\[ X + 2 - 2 = 0 \]
This simplifies to:
\[ X = 0 \]

### Step 6: Conclusion.
Thus, the oxidation number of the carbonyl carbon in methanal is 0.