CBSE Class 7 Science Exploring Substances: Acidic Basic and Neutral (Class 7 NCERT New) Quiz 4

1. The diagram shows the arrangement of apparatus used to study the reaction between hydrochloric acid and sodium hydroxide solution with phenolphthalein indicator, including a burette delivering acid to a flask containing sodium hydroxide. What is the name of the method shown in the diagram?

A Neutralisation B End point C Titration D Effervescence

2. The following information shows the properties of a liquid: Tastes bitter; Feels soapy; Has a pH value of 7.5. Which of the following is true about this liquid?

A It is slightly acidic. B It turns red litmus paper to blue. C It turns blue litmus paper to red. D It can react with iron to form a mixture.

3. Which of the following substances have the pH values of 2, 7 and 9 respectively?

A Baking soda; Distilled water; Lemon juice B Lemon juice; Baking soda; Distilled water C Distilled water; Lemon juice; Baking soda D Lemon juice; Distilled water; Baking soda

4. Anaqi dissolves the following substances in water separately: W Toothpaste, X Milk of magnesia, Y Vinegar, Z Shower cream. Which substances will turn the red litmus paper to blue?

A W B X, Y C W, X, Z D W, Y, Z

5. Which of the following is the difference between acid and alkali?

A Acid is bitter; Alkali is sour. B Acid changes moist red litmus paper to blue; Alkali changes moist blue litmus paper to red. C Acid reacts with metals to release hydrogen gas; Alkali reacts with ammonium salts to produce ammonia gas. D Acid has pH 8–14; Alkali has pH 1–6.

6. What are the products of neutralisation between hydrochloric acid and calcium hydroxide?

A Calcium chloride and water B Calcium carbonate and water C Calcium sulphate and hydrogen D Calcium chloride and hydrogen

7. Why is antacid used to relieve gastric pain?

A Antacid is less corrosive. B Antacid is alkaline to the stomach. C Antacid can kill microorganisms. D Antacid can neutralise excessive gastric juice.

8. The following information describes indicator M: Indicator M becomes colourless when tested with vinegar. What is indicator M?

A Universal indicator B Red litmus paper C Methyl orange indicator D Phenolphthalein indicator

9. Which of the following matches the correct colour change of litmus paper?

A Pickle — Red to Blue B Fertiliser — Red to Blue C Soap — Red to Red D Distilled water — Blue to Red

10. Which of the following is a neutralisation reaction?

A Sodium chloride + Calcium nitrate → Calcium chloride + Sodium nitrate B Carbon dioxide + Water → Oxygen + Glucose C Sulphuric acid + Potassium hydroxide → Potassium sulphate + Water D Calcium hydroxide + Calcium nitrate → Calcium hydroxide + Calcium nitrate