HCHO + CH3MgBr(grignard reagent) → C2H5OH (Ethanol) 

Conversion of Methanal to Ethanol

To convert methanal (also known as formaldehyde) to ethanol, we need to follow a two-step process: oxidation of methanal to methanoic acid (formic acid) and reduction of methanoic acid to ethanol.

Oxidation of Methanal to Methanoic Acid:
1. Oxidation using Tollens' reagent:
- Prepare Tollens' reagent by adding a small amount of silver nitrate to aqueous ammonia until the precipitate of silver oxide dissolves completely.
- Add methanal to the Tollens' reagent and heat the mixture gently.
- Methanal is oxidized to methanoic acid, which can be identified by the formation of a silver mirror on the inner surface of the container.

2. Oxidation using Fehling's solution:
- Prepare Fehling's solution by mixing equal volumes of Fehling's A (copper(II) sulfate) and Fehling's B (solution of sodium potassium tartrate in sodium hydroxide).
- Add methanal to Fehling's solution and heat the mixture.
- Methanal is oxidized to methanoic acid, and the blue color of Fehling's solution changes to a brick-red precipitate of copper(I) oxide.

Reduction of Methanoic Acid to Ethanol:
1. Reduction using Lithium Aluminum Hydride (LiAlH4):
- Dissolve methanoic acid in a dry solvent, such as ether or tetrahydrofuran (THF).
- Add a small amount of Lithium Aluminum Hydride (LiAlH4) to the solution and heat it under reflux.
- Methanoic acid is reduced to ethanol, and lithium aluminum hydride is converted to aluminum hydroxide.
- After the reaction, neutralize the excess LiAlH4 and any remaining acid with water.

2. Reduction using Sodium Borohydride (NaBH4):
- Dissolve methanoic acid in a solvent, such as methanol or ethanol.
- Add a small amount of Sodium Borohydride (NaBH4) to the solution and heat it under reflux.
- Methanoic acid is reduced to ethanol, and sodium borohydride is converted to sodium borate.
- After the reaction, neutralize the excess NaBH4 and any remaining acid with water.

Precautions:
- Handle the chemicals carefully and follow safety guidelines.
- Perform the reactions in a well-ventilated area or under a fume hood.
- Use appropriate protective equipment, such as gloves and goggles, to ensure personal safety.
- Dispose of the waste materials properly according to local regulations.

By following the above steps, methanal can be successfully converted to ethanol using either oxidation followed by reduction using appropriate reagents.

HCHO+CH3MgBr gives C2H5OH