Question

A student added a spoon full of powdered sodium hydrogen carbonate to a flask containing ethanoic acid. List two main observations he must note in his note book about the reaction that takes place. Also write chemical equations for the reaction.

Answer 1

Hint: To solve this we must know the nature of the substances that are reacting. This helps us to identify the type of reaction occurring. We are given that sodium hydrogen carbonate is added to ethanoic acid. Ethanoic acid as the name suggests is an acid whereas sodium hydrogen carbonate is a base.

Complete step-by-step answer:
We are given that a student added a spoon full of powdered sodium hydrogen carbonate to a flask containing ethanoic acid.Ethanoic acid as the name suggests is an acid whereas sodium hydrogen carbonate is a base. Ethanoic acid is also known as acetic acid.

The molecular formula of sodium hydrogen carbonate is ${\text{NaHC}}{{\text{O}}_{\text{3}}}$. The molecular formula of ethanoic acid is ${\text{C}}{{\text{H}}_{\text{3}}}{\text{COOH}}$.

When a student added a spoon full of powdered sodium hydrogen carbonate to a flask containing ethanoic acid, the reaction between acid and base occurred.

The reaction of sodium hydrogen carbonate with ethanoic acid is as follows:
${\text{NaHC}}{{\text{O}}_{\text{3}}} + {\text{C}}{{\text{H}}_{\text{3}}}{\text{COOH}} \to {\text{C}}{{\text{H}}_{\text{3}}}{\text{COONa}} + {{\text{H}}_2}{\text{O}} + {\text{C}}{{\text{O}}_2}$

In the reaction, sodium salt of ethanoic acid is produced. Along with it water is produced and carbon dioxide gas is evolved.The production of carbon dioxide gas shows brisk effervescence. Also, carbon dioxide is a colourless and odourless gas that evolved from the reaction mixture.

Thus, the two main observations that the student he must note in his note book about the reaction that takes place are as follows:
i) Brisk effervescence is observed.
ii) Colourless and odourless gas is evolved.

Note: We know that when an acid reacts with a base salt and water are produced in the reaction. The reaction is known as neutralization reaction. The reaction of sodium hydrogen carbonate with ethanoic acid produced sodium salt of ethanoic acid. Along with it water is produced as a by-product. Thus, it is a neutralization reaction.