CBSE – 10th Standard Science

Class 10 Question Bank Chapter 2 – Acids, Bases and Salts

Qus 1. Is turmeric a natural indicator?

Ans. Yes, turmeric is a natural indicator.

Qus 2. What are acid-base indicator?

Ans. The presence of acid or base in a solution. These are called acid-base indicators.

Qus 3. What are olfactory indicators?

Ans. When some substances whose odour changes in acidic or basic media. These are called olfactory indicators.

Qus 4. Name some different forms of calcium carbonate?

Ans. Limestone, chalk and marble are different forms of calcium carbonate.

Qus 5. Explain the term ‘neutralisation reaction’?

Ans. The reaction between an acid and a base to give a salt and water is known as a neutralisation reaction.

Qus 6. Which gas is commonly found in all acids and bases?

Ans. Hydrogen gas is commonly found in all acids and bases.

Qus 7. What are Alkalis?

Ans. Bases which are soluble in water are called alkalis.

Qus 8. Explain the process of Dilution?

Ans. Mixing an acid or base with water results in decrease in the concentration of ions. Such a process is

called dilution.

Qus 9. What is the use of Universal indicator?

Ans. Universal indicator is used to show different colours at different concentrations of hydrogen ions in a solution.

Qus 10. What is pH scale?

Ans. A scale for measuring hydrogen ion concentration in a solution is called Ph scale. The p in pH stands for ‘potenz’ in German,meaning power. On the pH scale we can measure pH generally from 0 (very acidic) to 14 (very alkaline). pH should be thought of simply as a number which indicates the acidic or basic nature of a solution. Higher the hydronium ion concentration, lower is the pH value

Qus 11. What is the pH value of a neutral solution?

Ans. The pH value of a neutral solution is 7.

Qus 12. Explain the meaning of Acid rain?

Ans. When pH of rain water is less than 5.6, it is called acid rain.

Qus 13. Which acid is found in our stomach?

Ans. Hydrochloric acid is found in our stomach.

Qus 14. What is tooth enamel made up of?

Ans. Tooth enamel is made up of calcium phosphate .

Qus 15. How is sodium chloride formed ?

Ans. Salt formed by the combination of hydrochloric acid and sodium hydroxide solution is called sodium chloride.

Qus 16. What is chlor-alkali process?

Ans. When electricity is passed through an aqueous solution of sodium chloride, it decomposes to form sodium hydroxide. The process is called the chlor-alkali process.

Qus 17. How is chlorine is produced?

Ans. Chlorine is produced during the electrolysis of aqueous sodium chloride.

Qus. 18. Write some uses of Bleaching powder in industries?

Ans. Bleaching powder  is used in bleaching cotton and linen in the textile industry and oxidising agent in many chemical industries.

Qus 19. What is used for removing permanent hardness of water?

Ans. Sodium carbonate is used for removing permanent hardness of water.

Qus 20. Write the chemical formula  for hydrated copper sulphate?

Ans. CuSO4.5H2O.