How is formic acid prepared ? 

Explanation

**Step-by-Step Solution for the Preparation of Formic Acid:**

1. **Starting Material**: The preparation of formic acid begins with methyl alcohol, which is also known as methanol (CH₃OH).

2. **First Oxidation Reaction**: The first step involves the oxidation of methanol. This is done using potassium dichromate (K₂Cr₂O₇) in the presence of sulfuric acid (H₂SO₄). The reaction can be represented as follows:
\[ \text{CH}_3\text{OH} \xrightarrow{\text{K}_2\text{Cr}_2\text{O}_7, \text{H}_2\text{SO}_4} \text{CH}_2\text{O} \]
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