Acids, Bases and Salts

Notes

A. Objective Questions (MCQs)

1. Which ion is produced by acids in aqueous solution?

A. OH⁻

B. H⁺

C. Na⁺

D. Cl⁻

Answer: B. H⁺

2. Which of the following is a natural indicator?

A. Phenolphthalein

B. Methyl Orange

C. Litmus

D. Universal Indicator

Answer: C. Litmus

3. Which gas is evolved when zinc reacts with hydrochloric acid?

A. Oxygen

B. Carbon dioxide

C. Hydrogen

D. Nitrogen

Answer: C. Hydrogen

4. The pH of a neutral solution is

A. 0

B. 5

C. 7

D. 14

Answer: C. 7

5. Which acid is present in vinegar?

A. Citric acid

B. Acetic acid

C. Hydrochloric acid

D. Nitric acid

Answer: B. Acetic acid

6. Which base is used in whitewashing?

A. NaOH

B. KOH

C. Ca(OH)₂

D. Mg(OH)₂

Answer: C. Calcium Hydroxide

7. Which salt is commonly known as baking soda?

A. Na₂CO₃

B. NaHCO₃

C. CaCO₃

D. NH₄Cl

Answer: B. NaHCO₃

8. Which substance is used in toothpaste to reduce acidity?

A. Acid

B. Base

C. Salt

D. Water

Answer: B. Base

9. Which indicator becomes pink in a basic solution?

A. Litmus

B. Turmeric

C. Phenolphthalein

D. Methyl Orange

Answer: C. Phenolphthalein

10. Neutralization reaction produces

A. Acid and Water

B. Salt and Water

C. Base and Water

D. Salt and Acid

Answer: B. Salt and Water

B. Very Short Answer Questions (1 Mark)

Q1. What is an acid?

Answer: An acid is a substance that produces H⁺ ions in aqueous solution.

Q2. What is a base?

Answer: A base is a substance that produces OH⁻ ions in aqueous solution.

Q3. Name one natural indicator.

Answer: Litmus.

Q4. What is the pH of pure water?

Answer: 7.

Q5. Which gas is evolved when an acid reacts with a metal?

Answer: Hydrogen gas.

Q6. Name one alkali.

Answer: Sodium hydroxide (NaOH).

Q7. What is neutralization?

Answer: The reaction between an acid and a base to form salt and water…