In which of the following the oxidation number of atom is/are correctly given ?

Options

A. `C_6H_(12)O_6:C=0`
B. `Na_(4)[Fe(CN)_6]:Fe=+3`
C. `HCOOH : C = + 4`
D. `HCHO : C = 0 `

Answer

To determine the correctness of the oxidation numbers provided in the options, we will analyze each compound step by step.

### Step 1: Analyze C6H12O6 (Glucose)
1. **Assign oxidation states**:
- Let the oxidation state of Carbon (C) be \( x \).
- Hydrogen (H) has an oxidation state of \( +1 \).
- Oxygen (O) has an oxidation state of \( -2 \).

2. **Set up the equation**:
- The molecule is neutral, so the sum of oxidation states must equal 0.
- There are 6 Carbon atoms, 12 Hydrogen atoms, and 6 Oxygen atoms.
- The equation becomes:
\[ 6x + 12(+1) + 6(-2) = 0 \]
- Simplifying this gives:
\[ 6x + 12 - 12 = 0 \implies 6x = 0 \implies x = 0 \]

3. **Conclusion**:
- The oxidation number of Carbon in C6H12O6 is 0, which is correctly given.

### Step 2: Analyze Na4Fe(CN)6
1. **Assign oxidation states**:
- Sodium (Na) has an oxidation state of \( +1 \).
- Cyanide (CN) has an oxidation state of \( -1 \).
- Let the oxidation state of Iron (Fe) be \( x \).

2. **Set up the equation**:
- The molecule is neutral, so:
\[ x + 4(+1) + 6(-1) = 0 \]
- Simplifying this gives:
\[ x + 4 - 6 = 0 \implies x - 2 = 0 \implies x = +2 \]

3. **Conclusion**:
- The oxidation number of Iron in Na4Fe(CN)6 is +2, but it is incorrectly stated as +3 in the option. Thus, this option is incorrect.

### Step 3: Analyze HCOOH (Formic Acid)
1. **Assign oxidation states**:
- Hydrogen (H) has an oxidation state of \( +1 \).
- Let the oxidation state of Carbon (C) be \( x \).
- Oxygen (O) has an oxidation state of \( -2 \).

2. **Set up the equation**:
- The molecule is neutral, so:
\[ 2(+1) + x + 2(-2) = 0 \]
- Simplifying this gives:
\[ 2 + x - 4 = 0 \implies x - 2 = 0 \implies x = +2 \]

3. **Conclusion**:
- The oxidation number of Carbon in HCOOH is +2, which is incorrectly given in the option. Thus, this option is incorrect.

### Step 4: Analyze HCHO (Formaldehyde)
1. **Assign oxidation states**:
- Hydrogen (H) has an oxidation state of \( +1 \).
- Let the oxidation state of Carbon (C) be \( x \).
- Oxygen (O) has an oxidation state of \( -2 \).

2. **Set up the equation**:
- The molecule is neutral, so:
\[ 2(+1) + x + (-2) = 0 \]
- Simplifying this gives:
\[ 2 + x - 2 = 0 \implies x = 0 \]

3. **Conclusion**:
- The oxidation number of Carbon in HCHO is 0, which is correctly given in the option.

### Final Answer:
- The oxidation numbers are correctly given in options **1 (C6H12O6)** and **4 (HCHO)**.