Question

${\text{Ethanol}}\xrightarrow{{{P_4}/{I_2}}}X\xrightarrow[{HBr}]{{KOH\left( {alc.} \right)}}Y$
In this sequence of reaction, Y is:
a.) Ethene
b.) Bromoethane
c.) Ethanol
d.) None of these

Answer 1

Hint: In this question, the ethanol is reacted with a series of reactants. We will proceed step by step reacting the ethanol as shown in the question. Phosphorus is a catalyst in the above reaction and alcoholic KOH is a reducing agent.

Complete answer:
In the reaction above, first the ethanol will react with iodine and undergoes a substitution reaction. The product of this reaction will be ethyl iodide. ${C_2}{H_5}OH\xrightarrow{{{P_4}/{I_2}}}{C_2}{H_5}I$ Now the ethyl iodide will react with alcoholic KOH and undergo elimination reaction and the product formed will be ethylene. ${C_2}{H_5}I\xrightarrow{{KOH\left( {alc.} \right)}}C{H_2} = C{H_2}$ Further ethylene will react with HBr and the product formed will be ethyl bromide. $C{H_2} = C{H_2}\xrightarrow{{HBr}}C{H_3}C{H_2}Br$ The final product formed is ethyl bromide which is also known as bromoethane.

Hence, the correct option is B. Additional Information- Ethanol is a natural byproduct of plant fermentation, which can also be manufactured by ethylene hydration.
Ethanol is always a liquid at room temperature, and has a melting point of 156 K and a boiling point of 351 K. It is among the most active ingredients in all alcoholic beverages. It is also used in the manufacture of many medicines such as cough syrups, tonics as well as iodine tincture, since it is an excellent solvent.
One of the most active components of all alcoholic beverages. Any part of ethanol in water is adequately soluble. Moreover, even a small amount of pure ethanol is fatal in consumption. Alcohol consumption has adverse effects on health for a long time.

Note: Ethanol is a dangerous chemical although it is commonly used. It is highly flammable and therefore has exact flash points that are important to know when it is used. Ethanol alone can cause coma and death, although it's used when drinking alcoholic beverages. Also it is necessary to take precautions while working with the chemicals.