In the reaction carried out between conc. Sulphuric acid and sodium chloride, which react with each other to form HCl gas. Blue litmus paper is brought near the mouth of the delivery tube to check the presence of HCl acid but no change is observed in the color of litmus paper because: *
a)The litmus paper used is dry
b) The litmus paper used is moist
c) Blue litmus paper does not change its color with an acid
d) The litmus paper is kept very close to the mouth of the delivery tube
Class 10
Answers
In the reaction carried out between conc. Sulphuric acid and sodium chloride, which react with each other to form HCl gas. Blue litmus paper is brought near the mouth of the delivery tube to check the presence of HCl acid but no change is observed in the color of litmus paper because: *
a)The litmus paper used is dry ☃️☃️
b) The litmus paper used is moist
c) Blue litmus paper does not change its color with an acid
d) The litmus paper is kept very close to the mouth of the delivery tube
Answer:
The litmus paper used is dry.
Explanation:
In the given reaction of sulphuric acid with sodium chloride , dry hydrochloric gas is evolved. In fact, dry hydrochloric gas is not an acid because it has no tendency to liberate hydrogen ions. When dry hydrochloric acid is passed through dry blue litmus paper, no variation in the colour of the litmus is observed. Even if the litmus is moist, dry hydrochloric gas on coming in contact with it will turn blue litmus red.