Solutions of Acids, Bases and Salts (Page No - 83 & 96) - Chemistry Lakhmir Singh, Class 10 | Extra Documents, Videos & Tests for Class 10 PDF Download

Question 63:
Hydrochloric acid reacts with a metal X to form a gas Y which bums with a ‘pop’ sound. Sodium hydroxide solution also reacts with the same metal X (on heating) to form the same gas Y.
(a) Name X and Y
(b) Write the chemical equation of the reaction of metal X with  (i) hydrochloric acid, and (ii) sodium hydroxide solution.
Solution :

 Page No:96

Question 1:
What is the chemical formula of (a) baking soda, and (b) washing soda ?
Solution :
(a) NaHCO₃.
(b) Na₂CO₃.

Question 2:
Write the chemical formula of (i) soda ash, and (ii) sodium carbonate decahydrate.
Solution :
(i) Na₂CO₃.
(ii) Na₂CO₃.10H₂O.

Question 3:
State whether the following statement is true or false :
Copper sulphate crystals are always wet due to the presence of water of crystallisation in them.
Solution :
False.

Question 4:
Which of the following salt has a blue colour and why ?
CuSO₄.5H₂O or CuSO₄
Solution :
CuSO₄.5H₂O
has blue colour due to the presence of water of crystallization.

Question 5:
What would be the colour of litmus in a solution of sodium carbonate ?
Solution :
Blue.

Question 6:
State the common and chemical names of the compound formed when plaster of Paris is mixed with water.
Solution :
The common name is Gypsum and the chemical name is calcium sulphate dihydrate.

Question 7:
With which substance should chlorine be treated to get bleaching powder ?
Solution :
Calcium hydroxide.

Question 8:
What is the commercial name of calcium sulphate hemihydrate ?
Solution :
Plaster of Paris.