Acids, Bases and Salts

Which of the following has the highest pH value?

1. Hydrochloric acid
2. Lemon juice
3. Pure water
4. Sodium hydroxide solution

Which compound is known as plaster of Paris?

1. Calcium sulphate hemihydrate
2. Sodium carbonate
3. Calcium chloride
4. Sodium bicarbonate

Which acid is present in the stomach?

1. Acetic acid
2. Hydrochloric acid
3. Citric acid
4. Formic acid

Which substance is used to treat acidic soil?

1. Vinegar
2. Lime
3. Hydrochloric acid
4. Sodium chloride

Which gas is released when baking soda reacts with an acid?

1. Hydrogen
2. Oxygen
3. Carbon dioxide
4. Nitrogen

What is the chemical formula of common salt?

1. NaCl
2. NaOH
3. HCl
4. CaCO3

Which indicator gives a pink colour in a basic solution?

1. Methyl orange
2. Phenolphthalein
3. Blue litmus
4. Turmeric

What is formed when hydrochloric acid reacts with sodium hydroxide?

1. Salt and water
2. Hydrogen gas
3. Carbon dioxide
4. Oxygen gas

Which acid is present in vinegar?

1. Hydrochloric acid
2. Sulphuric acid
3. Acetic acid
4. Nitric acid

What happens when an acid reacts with a metal?

1. Oxygen gas is released
2. Hydrogen gas is released
3. Nitrogen gas is released
4. Carbon dioxide is released

Which of the following substances turns blue litmus paper red?

1. Sodium hydroxide
2. Hydrochloric acid
3. Baking soda
4. Calcium hydroxide

Why is the pH of soil important for agriculture?

1. It determines the color of soil only
2. It affects nutrient availability and plant growth
3. It increases rainfall
4. It reduces sunlight

Why do acids show acidic behavior only in aqueous solutions?

1. They release hydrogen ions only in the presence of water
2. They become solids in water
3. Water neutralizes acids completely
4. Acids cannot exist without water

Which salt is commonly used in baking powder?

1. Sodium chloride
2. Sodium bicarbonate
3. Potassium nitrate
4. Calcium sulfate

Which of the following is a common base?

1. Sulfuric acid
2. Nitric acid
3. Sodium hydroxide
4. Hydrochloric acid

What is the pH value of a neutral solution?

1. 0
2. 7
3. 10
4. 14

What is formed when an acid reacts with a base?

1. Salt and water
2. Oxygen and water
3. Hydrogen gas
4. Carbon dioxide

Which ion is responsible for the acidic nature of a solution?

1. OH⁻
2. Na⁺
3. H⁺
4. Cl⁻

What is produced when an acid reacts with a metal?

1. Oxygen gas
2. Hydrogen gas and a salt
3. Water only
4. Carbon dioxide only

Which indicator turns pink in a basic solution?

1. Blue litmus
2. Red litmus
3. Phenolphthalein
4. Methyl orange

Which of the following is an acid?

1. Sodium hydroxide
2. Hydrochloric acid
3. Calcium oxide
4. Ammonia