Introduction:
Ethyl bromide, also known as bromoethane, is a chemical compound that can be synthesized from ethyl alcohol. This process involves the substitution of a hydroxyl group (-OH) in ethyl alcohol with a bromine atom (-Br) to form the ethyl bromide molecule. The reaction is carried out in the presence of a strong acid catalyst, usually sulfuric acid (H2SO4).

Step-by-step synthesis of ethyl bromide from ethyl alcohol:

1. Preparation of reactants:
- Obtain ethyl alcohol (C2H5OH) as the starting material for the synthesis.
- Ensure the ethyl alcohol is pure and free from any impurities that may interfere with the reaction.

2. Setup of reaction:
- In a round-bottom flask, add a measured amount of ethyl alcohol.
- Add a few drops of concentrated sulfuric acid (H2SO4) to the flask.
- The sulfuric acid acts as a catalyst in the reaction, promoting the substitution of the hydroxyl group with a bromine atom.

3. Reaction:
- Heat the reaction mixture gently using a heating mantle or a water bath.
- The heat accelerates the reaction, facilitating the removal of a water molecule (H2O) from the ethyl alcohol molecule.
- The sulfuric acid catalyst aids in the dehydration process by abstracting the hydroxyl group as a water molecule.

4. Addition of bromine:
- Once the dehydration is complete, slowly add liquid bromine (Br2) dropwise to the reaction flask.
- The bromine atom replaces the hydroxyl group in the ethyl alcohol molecule, resulting in the formation of ethyl bromide (C2H5Br).

5. Separation and purification:
- After the reaction, the mixture contains the desired ethyl bromide along with unreacted starting materials and by-products.
- The reaction mixture is poured into a separating funnel and allowed to stand until the layers separate.
- The lower organic layer containing ethyl bromide is carefully separated.
- The separated ethyl bromide is then washed with water to remove any traces of sulfuric acid or impurities.
- The ethyl bromide is dried by using anhydrous sodium sulfate (Na2SO4) or another suitable drying agent.
- Finally, the purified ethyl bromide can be distilled to obtain a more concentrated and pure product.

Conclusion:
Ethyl bromide can be synthesized from ethyl alcohol through a substitution reaction, where the hydroxyl group is replaced with a bromine atom. This process involves the use of sulfuric acid as a catalyst and liquid bromine as the bromine source. Proper separation and purification techniques are essential to obtain high-quality ethyl bromide.