Question

The formulae of four organic compounds are given below:

A B C D

C2H4 CH3COOH C2H5OH C2H6

(i) Which one of these compounds A, B, C or D is a saturated hydrocarbon?

(ii) Identify the organic acid and give its structural formula.

(iii) Which of the above compounds when heated at 443K in the presence of

concentrated H2SO4 forms ethene as the major product? What is the role played by

concentrated H2SO4 in this reaction? Also write the chemical equation involved.

(iv) Give a chemical equation when B and C react with each other in presence of

concentrated H2SO4. Name the major product formed and mention one of its

important use.​

Answer 1

Answer:

(i)C2H6

(ii)CH3COOH

Explanation:

(i)Because it is alkane CnH2n+2

(ii)CH3COOH

H O

| ||

H-C-C-O-H

|

H

Answer 2

Explanation:

(i) Saturated hydrocarbons are the one which has only single bond with in the carbon atoms.

Compound D which is ethane is a saturated hydrocarbon.

(ii) Compound B which is ethanoic acid is an organic acid as it has carboxylic acid group -COOH.

The structural formula is:

      H      O

       |        ||

H -   C  -  C - O - H

        |

       H

(iii) Compound C which is ethanol. On heating, it gives ethene as the major product. The reaction is shown below as:

C₂H₅OH $\xrightarrow[H_2SO_4]{Heat}$ C₂H₄ + H₂O

$H_2SO_4$ acts as a dehydrating agent which eliminates water from ethanol. It acts as catalyst.

(iv) On reacting compound B and C, ethanoic acid and ethanol, it give ester, ethyl ethanoate. They are sweet smelling compounds and used as artificial flavoring agents.