Baking Soda (Preparation) MCQs Quiz | Class 10

Test your understanding of Class X Science (Code 086) Unit I: Chemical Substances – Nature and Behaviour. This quiz focuses on Baking Soda (Preparation), covering its preparation method, chemical equations, and basic composition awareness. Attempt the 10 MCQs below, submit to check your score, and download the answer sheet PDF for your records.

About Baking Soda Preparation

Baking Soda, chemically known as Sodium Hydrogen Carbonate (NaHCO3), is a staple in households and laboratories. It is primarily produced using the Solvay process. This section provides a detailed overview of its preparation, properties, and uses relevant to the Class 10 Science curriculum.

1. Chemical Name and Formula

The chemical name is Sodium Hydrogen Carbonate (also called Sodium Bicarbonate). Its chemical formula is NaHCO3.

2. Preparation Method (Solvay Process)

Baking soda is produced by reacting a cold and concentrated solution of sodium chloride (brine) with ammonia and carbon dioxide. The reaction precipitates sodium hydrogen carbonate because it is sparingly soluble in water.

The Chemical Equation:
NaCl + H2O + CO2 + NH3 → NH4Cl + NaHCO3

  • Reactants: Sodium Chloride (NaCl), Water (H2O), Carbon Dioxide (CO2), Ammonia (NH3).
  • Products: Ammonium Chloride (NH4Cl) and Sodium Hydrogen Carbonate (NaHCO3).

3. Effect of Heat

When baking soda is heated during cooking, it undergoes thermal decomposition to release carbon dioxide gas, which causes dough to rise. This reaction also produces sodium carbonate.

Reaction on Heating:
2NaHCO3 + Heat → Na2CO3 + H2O + CO2

4. Key Properties

  • It is a mild, non-corrosive basic salt.
  • It appears as white crystals but is sparingly soluble in water.
  • Its aqueous solution turns red litmus blue (alkaline nature).

Quick Revision List

  • Common Name: Baking Soda
  • Process: Reaction of brine with CO2 and NH3.
  • Role in Baking Powder: Mixed with a mild edible acid like tartaric acid to neutralize bitterness of Na2CO3.
  • Uses: Antacid (neutralizes stomach acid), soda-acid fire extinguishers, ingredient in baking.

Extra Practice Questions

1. Why is tartaric acid added to baking powder? (Ans: To neutralize the bitter taste of sodium carbonate formed during heating).
2. Is the pH of sodium hydrogen carbonate solution less than or greater than 7? (Ans: Greater than 7, as it is basic).
3. What is the main byproduct of the Solvay process? (Ans: Ammonium Chloride).
4. Name the gas evolved when baking soda is heated. (Ans: Carbon Dioxide).
5. Which fire extinguisher uses baking soda? (Ans: Soda-acid fire extinguisher).