Chemistry · Chapter 7 of 11

Acids, Bases & Salts: BPSC & UPPCS Prelims PYQs

12 previous-year questions on Acids, Bases & Salts. Each one opens to its answer and explanation.

1. 1. 71st BPSC Prelims 2025

   pH value of 0.1N HCl solution is approximately:

   1. A11.0
   2. B1.0
   3. C10
   4. D2.0
   Answer and explanation →

2. 2. UPPSC Prelims 2025

   With reference to 'acid and bases', which of the following statements is/are correct?
   1. Acidic solutions have pH more than 7.
   2. Basic solutions have pH less than 7.
   Select the correct answer from the code given below:

   1. AOnly 1
   2. BBoth 1 and 2
   3. CNeither 1 nor 2
   4. DOnly 2
   Answer and explanation →

3. 3. 70th BPSC Prelims 2024

   Sour taste of vinegar is due to

   1. ATartaric acid
   2. BLactic acid
   3. CCitric acid
   4. DNone of these
   Answer and explanation →

4. 4. 68th BPSC Prelims 2023

   Some metal oxides react with acid as well as a base to produce salt and water. They are known as amphoteric oxides. Examples of amphoteric oxides are

   1. ACuO and ZnO
   2. BAl2O3 and ZnO
   3. CAl2O3 and CuO
   4. DMore than one of the above
   5. ENone of the above
   Answer and explanation →

5. 5. 68th BPSC Prelims 2023

   Acids react with metal carbonates to liberate ______ gas.

   1. AH2
   2. BCO2
   3. CCO
   4. DMore than one of the above
   5. ENone of the above
   Answer and explanation →

6. 6. 68th BPSC Prelims 2023

   You have been provided with three test tubes. One of them contains distilled water and the other two contain an acidic solution and a basic solution, respectively. Which of them will turn red litmus to blue?

   1. ADistilled water
   2. BAcid
   3. CBase
   4. DMore than one of the above
   5. ENone of the above
   Answer and explanation →

7. 7. 68th BPSC Prelims 2023

   Why does dry HCl gas not change the colour of dry litmus paper?

   1. AHCl gas acts as a dehydrating agent.
   2. BBlue litmus becomes dry in the presence of dry HCl gas.
   3. CNo H3O+ ions are present. Litmus changes colour only in the presence of H3O+ ions.
   4. DMore than one of the above
   5. ENone of the above
   Answer and explanation →

8. 8. 67th BPSC Prelims 2022

   Which among the following solutions has pH value more than 7?

   1. ABuffer solution
   2. BBasic solution
   3. CAcidic solution
   4. DNeutral solution
   5. ENone of the above / More than one of the above
   Answer and explanation →

9. 9. UPPSC Prelims 2021

   Which of the following is NOT correctly matched?

   1. AAcid present in vinegar - Acetic acid
   2. BCompound present in bones - Calcium
   3. CSouring of milk - Nitric acid
   4. DAcid present in gastric juice - Hydrochloric acid
   Answer and explanation →

10. 10. 66th BPSC Prelims 2020

    The pH of a solution changes from 3 to 6. The H+ ion concentration will

    1. Aincrease 3 times
    2. Bdecrease 3 times
    3. Cdecrease 10 times
    4. Ddecrease 1000 times
    5. ENone of the above / More than one of the above
    Answer and explanation →

11. 11. 65th BPSC Prelims 2019

    The pH value of water is

    1. A4
    2. B7
    3. C12
    4. D18
    5. ENone of the above / More than one of the above
    Answer and explanation →

12. 12. UPPSC Prelims 2017 Asked again

    Which one of the following organic acids is abundant in grapes, tamarind and banana?

    1. AAcetic acid
    2. BCitric acid
    3. CLactic acid
    4. DTartaric acid
    Answer and explanation →