Dry HCl gas and dry litmus paper
This type of question, asked 3 times: 2023, 2025, 2026. All 3 questions below, oldest first.
Try each one first, then open its answer.
Question 1
2023
28(i) Suggest a safe procedure of diluting a strong concentrated acid. (ii) Name the salt formed when sulphuric acid is added to sodium hydroxide and write its pH. (iii) Dry gas does not change the colour of dry blue litmus paper. Why ?Question 2
2025
22(a) Write the formula of the ions which (i) acids, and (ii) bases generate in water solutions. (b) Dry gas does not change the colour of dry litmus paper. Why ?Question 3
2026
27 (a)Give reasons : (i) For dilution of an acid, acid is added into water and not water into acid. (ii) Dry gas does not turn blue litmus red whereas dilute hydrochloric acid does. (iii) Blue colour of Copper(II) sulphate crystals turns white on heating.