In the reaction `CH_(3)OHrarrHCOOH`, the number of electrons that must be added to the right is :-

Options

A. 4
B. 3
C. 2
D. 1

Explanation

To determine the number of electrons that must be added to the right in the reaction \( \text{CH}_3\text{OH} \rightarrow \text{HCOOH} \), we will follow these steps:

### Step 1: Write the unbalanced reaction
The unbalanced reaction is:
\[ \text{CH}_3\text{OH} \rightarrow \text{HCOOH} \]

### Step 2: Count the number of atoms on both sides
- On the left side (reactant side):
- Carbon (C): 1 (from CH₃OH)
- Hydrogen (H): 4 (3 from CH₃ and 1 from OH)
- Oxygen (O): 1 (from OH)

- On the right side (product side):
- Carbon (C): 1 (from HCOOH)
- Hydrogen (H): 2 (from HCOOH)
- Oxygen (O): 2 (from HCOOH)

### Step 3: Balance the hydrogen atoms
To balance the hydrogen atoms, we note that there are 4 hydrogen atoms on the left and only 2 on the right. We can add water (H₂O) to the right side:
\[ \text{CH}_3\text{OH} \rightarrow \text{HCOOH} + \text{H}_2\text{O} \]

Now, let's recount the atoms:
- Left: C = 1, H = 4, O = 1
- Right: C = 1, H = 4 (2 from HCOOH and 2 from H₂O), O = 3 (2 from HCOOH and 1 from H₂O)

### Step 4: Balance the oxygen atoms
Now we have 3 oxygen atoms on the right side and only 1 on the left. To balance the oxygen, we can add 2 more water molecules to the right side:
\[ \text{CH}_3\text{OH} \rightarrow \text{HCOOH} + 2 \text{H}_2\text{O} \]

Now, recount the atoms:
- Left: C = 1, H = 4, O = 1
- Right: C = 1, H = 6 (2 from HCOOH and 4 from 2 H₂O), O = 5 (2 from HCOOH and 2 from 2 H₂O)

### Step 5: Adjust the hydrogen and oxygen balance
To balance the hydrogen atoms, we can add 4 \( \text{H}^+ \) ions to the left side:
\[ \text{CH}_3\text{OH} + 4 \text{H}^+ \rightarrow \text{HCOOH} + 2 \text{H}_2\text{O} \]

Now recount:
- Left: C = 1, H = 8 (4 from H⁺ and 4 from CH₃OH), O = 1
- Right: C = 1, H = 6, O = 3

### Step 6: Balance the charges
To balance the charges, we need to add 4 electrons to the right side:
\[ \text{CH}_3\text{OH} + 4 \text{H}^+ + 4 e^- \rightarrow \text{HCOOH} + 2 \text{H}_2\text{O} \]

### Conclusion
The number of electrons that must be added to the right is 4.

### Final Answer
The number of electrons that must be added to the right is **4**.

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