Question

Observe the table below:

Students	Color of acetic acid	Odor of acetic acid	Action with sodium hydrogen carbonate
(A)	Blue	Fruity	Gas evolves without bubbles
(B)	Colorless	Smell of vinegar	Effervescence
(C)	Light green	Odorless	Gas evolves without bubbles
(D)	Light brown	Rotten egg	Effervescence

Four students observed the color and odor of acetic acid in its reaction with sodium hydrogen carbonate. They tabulated their observations as above. The correct set of observations is that of student:
A. (A)
B. (B)
C. (C)
D. (D)

Answer 1

Hint:Acetic acid is a colorless organic compound belonging to the carboxylic acid family and its alternate name is ethanoic acid. Vinegar is no less than $$4\mathrm{\%}$$ acetic acid by volume, making acetic acid the main component of vinegar apart from water. Acetic acid has a distinctive sour taste and pungent smell. Thus, the acetic acid can also be said to have vinegar like smell, reversibly.

Complete step by step answer:
Acetic acid is the second simplest carboxylic acid (after formic acid). It consists of a methyl group attached to a carboxyl group. It is an important chemical reagent and industrial chemical, used primarily in the production of cellulose acetate for photographic film, polyvinyl acetate for wood glue, and synthetic fibres and fabrics. In households, diluted acetic acid is often used in descaling agents.
Sodium bicarbonate or sodium hydrogen carbonate is a chemical compound with the chemical formula $NaHC{O}_3$ . Sodium bicarbonate is a white crystalline solid, but often appears as a fine powder. It has a slightly salty, alkaline taste resembling that of washing soda (sodium carbonate).
The reaction of acetic acid along with sodium bicarbonate is as follows:
$C{H}_{3}COOH+NaHC{O}_3\to C{H}_{3}COONa+C{O}_2+H_{2}O$
Carbon dioxide formed in the reaction is released with a hiss sound which is known as effervescence. Thus, the observations from the reactants and the reaction are that:
(i) Acetic acid is a colorless liquid.
(ii) It has a smell like vinegar.
(iii) On the action of acetic acid with sodium hydrogen carbonate, carbon dioxide is released with effervescence.

Thus, the correct option is B.

Note:The reaction of acetic acid with sodium hydrogen carbonate is a partial neutralization reaction where the acetic acid which is a weak acid is neutralized by the sodium hydrogen carbonate to yield a salt of sodium acetate and a release of a water molecule along with carbon dioxide takes place.