Answer the following Questions :-
1. How does an acid taste?
2. Is calcium hydroxide an acid or base?
3. What is Neutralisation? Give an example.
4. List the properties of caustic soda.
5. Differentiate between acidic oxides and basic oxides with examples.
6. Is KOH an alkali? How can you say that without experimentally testing your result?
7. Write balanced equations for the reactions of (a) Zinc with Hydrochloric acid (b) Magnesium with Sulphuric acid.
8. Give two differences between an Acid and a Base.
9. What is an Indicator? Give two examples alongwith their action.
10. State three general properties of acids.
Answers
1). How does an acid taste?
⇒An acid tastes sour.
2). Is calcium hydroxide an acid or base?
⇒Calcium hydroxide is a base. Infact, it is a strong alkali. Its chemical formula is Ca(OH)₂.
3). What is Neutralisation? Give an example.
⇒Neutralisation is the reaction between an acid and a base to form salt and water.
Hydrochloric Acid + Sodium Hydroxide → Sodium Chloride + Water
i.e. HCl + NaOH → NaCl + H₂O
4). List the properties of caustic soda.
⇒ i) Caustic Soda (NaOH) is a strong alkali.
ii) It is corrosive in nature.
iii) It is soapy to touch.
iv) It turns red litmus blue, being basic in nature.
5). Differentiate between acidic oxides and basic oxides with examples.
⇒ i) Acidic oxides are oxides of non-metals such as: Carbon dioxide, Sulphur dioxide, etc. while basic oxides are oxides of metals such as: Calcium oxide, Magnesium oxide, etc.
ii) Acidic oxides react with water to form acids such as: Carbonic Acid (H₂CO₃), Sulphuric Acid (H₂SO₄), etc. while basic oxides react with water to form bases such as: Calcium hydroxide [Ca(OH)₂], Magnesium hydroxide [Mg(OH)₂], etc.
6). Is KOH an alkali? How can you say that without experimentally testing your result?
⇒ Yes, KOH is an alkali. We can say this by dissolving KOH in water. We will see that KOH is soluble in water.
7). Write balanced equations for the reactions of (a) Zinc with Hydrochloric acid (b) Magnesium with Sulphuric acid.
⇒(a) Zinc + Hydrochloric Acid → Zinc Chloride + Hydrogen ↑
i.e. Zn + 2HCL → ZnCl₂ + H₂ ↑
(b) Magnesium + Sulphuric Acid → Magnesium Sulphate + Hydrogen ↑
i.e. Mg + H₂SO₄ → MgSO₄ + H₂ ↑
8). Give two differences between an Acid and a Base.
⇒ i) An acid tastes sour while a base tastes bitter.
ii) An acid changes blue litmus into red and a base changes red litmus into blue.
9).What is an Indicator? Give two examples alongwith their action.
⇒ An indicator is a substance which is used to test for a base or an acid.
i) Litmus
⇒ Blue litmus turns red when it is added to an acid. Red litmus turns blue when it is added to a base.
ii) Phenolphthalein
⇒ It remains colourless when the solution is acidic and turns magenta or pink when the solution is basic.
10).State three general properties of acids.
⇒Three general properties of acid are:
i) An acid tastes sour.
ii) An acid is corrosive in nature.
iii) An acid turns blue litmus red.
Answer the following Questions :-
1. How does an acid taste?
2. Is calcium hydroxide an acid or base?
3. What is Neutralisation? Give an example.
4. List the properties of caustic soda.
5. Differentiate between acidic oxides and basic oxides with examples.
6. Is KOH an alkali? How can you say that without experimentally testing your result?
7. Write balanced equations for the reactions of (a) Zinc with Hydrochloric acid (b) Magnesium with Sulphuric acid.
8. Give two differences between an Acid and a Base.
9. What is an Indicator? Give two examples alongwith their action.
10. State three general properties of acids.