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
Answer:
1) sour
2) base
3) when acid and base interact with each other is called Neutralisation. for ex -
HCl+ NaOH = NaCl+ Water.
4) class 10 science book page no. 31 uses of baking soda.
8) Acids - they are sour in taste
they turn blue litmus to red
base- they are bitter in taste
they turn red litmus paper into blue.
Answer- The above questions are from the chapter 'Acids, Bases and Salts.'
Given question: 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 along with their action.
10. State three general properties of acids.
Answer- 1. An acid tastes sour.
2. Calcium hydroxide is a base. Infact, it is a strong alkali. Its chemical formula is Ca(OH)₂.
3. 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. 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. 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. Yes, KOH is an alkali. We can say this by dissolving KOH in water. We will see that KOH is soluble in water.
7. (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. 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. 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. 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.