Important Questions (1 Mark): Acids, Bases & Salts - Class 10

As the solution turns red litmus solution blue, it must be basic. To reverse the change, we must add an acid.

2NaCl + 2H₂O → 2NaOH + H₂ + Cl₂
(Chlor-alkali process)

Tartaric acid is a leavening agent which is mixed with baking powder to neutralize the bitterness produced by baking powder. It is an important food additive that is being used today. When dry base powder is added to acid forming a solution, it is mixed with cream of tartar which is chemically known as potassium bitartrate. 

Ca(OH)₂ + Cl₂ → CaOCl₂ + H₂O 
(Manufacturing of bleaching powder)

Only a basic solution will change the colour of pH paper to greenish-blue.

and out of all these, only antacid is a base.

lemon juice and vinegar are acid

common salt is neutral 

Ag₂S + H₂SO₄ → Ag₂SO₄ + H₂S  (Double displacement reaction)

Acids possess sour taste and turn blue litmus paper red.

pH of H₂O is 7 because it is neutral. It is formed by neutralization reaction.

Hydrochloric acid ionises as follows :
HCl→ H⁺ +Cl^- 
H⁺ ions combine with water molecules to form H₃O⁺. Therefore, the ions present in dilute aqueous solution of hydrochloric acid are H₃O⁺ and Cl^-.

Sodium hydrogen carbonate also known as sodium bicarbonate is produced by chemical reaction between weak acid and strong base.
The acid is Hydrochloric Acid (HCl) and the base is Na₂CO₃ 

Na₂CO₃ + HCl = NaHCO₃ + NaCl