Verified answer

Required Answers:-

1. An acid is sour in taste.

________________________________

2. A calcium hydroxide is a base which is also known as Slaked lime.

Calcium hydroxide has the formula Ca(OH)₂. It is formed when CaO (Calcium Oxide) reacts with water (H₂O).

________________________________

3. Neutralisation is a reaction in which acids and bases react with each other to neutralize themselves. The products of this reaction are mainly salt and water.

________________________________

4. Uses of Caustic Soda (or Sodium Hydroxide, NaOH):-

• NaOH is used to manufacture soap, detergents, etc.
• It is used for degreasing metals.
• NaOH is used ti purify bauxite.

________________________________

5. Differences between acidic oxide and basic oxide are as follows:-

Acidic Oxides:-

• Acidic oxides dissociate in water to give acid.
• Non-metals react with oxygen to give out metallic oxide.

Basic Oxides:-

• Basic oxides dissociate in water to form bases (commonly known as alkali).
• Metals react with oxygen to produce basic oxides.

________________________________

6. Yes, KOH (Potassium Hydroxide) is a base. It is because it contains hydroxide ion or OH⁻ ion. We know, hydroxide ion is only present in the case of bases.

________________________________

7. (a) Zn + 2HCl → ZnCl₂ + H₂

(b) Mg + H₂SO₄ → MgSO₄ + H₂

________________________________

8. Differences between acids and bases:-

Acids:-

• Acids when dissociated in water produce H⁺ ion.
• Acids turn blue litmus red.

Bases:-

• Bases when dissociated jn water produce OH⁻ ion.
• Bases turn red litmus blue.

________________________________

9. An indicator helps us to determine whether a substance is acidic, basic or neutral in nature.

Eg:-

(i) Litmus paper:-

• Acid - Blue litmus red
• Base - Red litmus blue

(ii) Methyl Orange Solution:-

• Acid - Orange color becomes red
• Base - Orange color becomes yellow.

________________________________

10. Three general properties of acids are:-

• Acids are generally sour in taste.
• According to Arrhenius concept of acids, acids dissociate in water to produce H⁺ (or hydrogen) ion.
• Acids turn blue litmus red, methyl orange solution red, phenolphthalein solution colourless.

________________________________

Required Answers:-

1. An acid is sour in taste.

________________________________

2. A calcium hydroxide is a base which is also known as Slaked lime.

Calcium hydroxide has the formula Ca(OH)₂. It is formed when CaO (Calcium Oxide) reacts with water (H₂O).

________________________________

3. Neutralisation is a reaction in which acids and bases react with each other to neutralize themselves. The products of this reaction are mainly salt and water.

________________________________

4. Uses of Caustic Soda (or Sodium Hydroxide, NaOH):-

NaOH is used to manufacture soap, detergents, etc.

It is used for degreasing metals.

NaOH is used ti purify bauxite.

________________________________

5. Differences between acidic oxide and basic oxide are as follows:-

Acidic Oxides:-

Acidic oxides dissociate in water to give acid.

Non-metals react with oxygen to give out metallic oxide.

Basic Oxides:-

Basic oxides dissociate in water to form bases (commonly known as alkali).

Metals react with oxygen to produce basic oxides.

________________________________

6. Yes, KOH (Potassium Hydroxide) is a base. It is because it contains hydroxide ion or OH⁻ ion. We know, hydroxide ion is only present in the case of bases.

________________________________

7. (a) Zn + 2HCl → ZnCl₂ + H₂

(b) Mg + H₂SO₄ → MgSO₄ + H₂

________________________________

8. Differences between acids and bases:-

Acids:-

Acids when dissociated in water produce H⁺ ion.

Acids turn blue litmus red.

Bases:-

Bases when dissociated jn water produce OH⁻ ion.

Bases turn red litmus blue.

________________________________

9. An indicator helps us to determine whether a substance is acidic, basic or neutral in nature.

Eg:-

(i) Litmus paper:-

Acid - Blue litmus red

Base - Red litmus blue

(ii) Methyl Orange Solution:-

Acid - Orange color becomes red

Base - Orange color becomes yellow.

________________________________

10. Three general properties of acids are:-

Acids are generally sour in taste.

According to Arrhenius concept of acids, acids dissociate in water to produce H⁺ (or hydrogen) ion.

Acids turn blue litmus red, methyl orange solution red, phenolphthalein solution colourless.

________________________________