Convert HCHO to glycol in one step only.

Explanation

To convert formaldehyde (HCHO) to glycol (ethylene glycol, C2H6O2) in one step, we can utilize the pinacol reaction. Here’s a step-by-step breakdown of the process:

### Step 1: Understand the Reactants and Products
- **Reactant**: HCHO (formaldehyde) is a simple aldehyde with the structure H2C=O.
- **Product**: Glycol (ethylene glycol) has the structure HO-CH2-CH2-OH.

### Step 2: Identify the Reaction Type
- The pinacol reaction involves the conversion of a carbonyl compound (like an aldehyde) into a glycol through a radical mechanism. In this case, we will be converting formaldehyde into glycol.
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