Acids, Bases and Salts MCQ Quiz

30 questions

1. Acids produce which ion in aqueous solution?

   1. OH⁻
   2. H⁺ (H3O⁺)
   3. Cl⁻
   4. Na⁺

2. Bases produce which ion in aqueous solution?

   1. H⁺
   2. OH⁻
   3. H3O⁺
   4. CO3²⁻

3. The pH of a neutral solution is

   1. 0
   2. 7
   3. 14
   4. 1

4. As acidity increases, pH

   1. increases
   2. decreases
   3. stays 7
   4. becomes 14

5. Litmus is a natural indicator obtained from

   1. roses
   2. lichens
   3. turmeric
   4. onions

6. Chemical formula of washing soda is

   1. Na2CO3
   2. Na2CO3·10H2O
   3. NaHCO3
   4. Na2SO4

7. Chemical name of baking soda is

   1. sodium carbonate
   2. sodium hydrogencarbonate
   3. sodium hydroxide
   4. calcium carbonate

8. Plaster of Paris is

   1. CaSO4·2H2O
   2. CaSO4·½H2O
   3. CaSO4
   4. CaCO3

9. Setting of Plaster of Paris involves

   1. oxidation
   2. hydration
   3. reduction
   4. fermentation

10. Bleaching powder formula is

    1. CaCl2
    2. CaOCl2
    3. Ca(OH)2
    4. CaCO3

11. Which gas turns lime water milky?

    1. O2
    2. CO2
    3. H2
    4. Cl2

12. Tooth decay begins when mouth pH falls below

    1. 7
    2. 5.5
    3. 9
    4. 12

13. Antacids work by

    1. oxidising acid
    2. neutralising excess acid
    3. reducing acid
    4. diluting only

14. Dry HCl gas does not turn dry litmus red because

    1. it is basic
    2. no H⁺ ions without water
    3. it is neutral
    4. litmus is dry

15. A salt of strong acid and strong base has pH

    1. less than 7
    2. equal to 7
    3. more than 7
    4. 0

16. Which salt is used to remove permanent hardness of water?

    1. baking soda
    2. washing soda
    3. bleaching powder
    4. POP

17. Tartaric acid is added to baking powder to

    1. increase pH
    2. neutralise bitter Na2CO3
    3. add colour
    4. preserve

18. The chlor-alkali process electrolyses

    1. molten NaCl
    2. brine (aqueous NaCl)
    3. water
    4. HCl

19. Gas produced at the cathode in chlor-alkali process is

    1. Cl2
    2. H2
    3. O2
    4. CO2

20. Acid found in curd/sour milk is

    1. acetic acid
    2. lactic acid
    3. citric acid
    4. tartaric acid

21. Assertion: Water of crystallisation is absent in bleaching powder. Reason: It has a fixed number of water molecules.

    1. Both true, R explains A
    2. Both true, R not explanation
    3. A true, R false
    4. A false, R true

22. Universal indicator shows red for a solution of pH

    1. 1
    2. 7
    3. 10
    4. 14

23. Metal carbonate + acid gives

    1. H2 gas
    2. CO2 gas
    3. O2 gas
    4. Cl2 gas

24. Copper oxide + dilute HCl gives a solution that is

    1. colourless
    2. bluish-green
    3. red
    4. yellow

25. Which is used in soda-acid fire extinguishers?

    1. NaOH
    2. NaHCO3
    3. Na2CO3
    4. CaOCl2

26. When an acid reacts with a metal, the product besides salt is

    1. oxygen
    2. hydrogen
    3. water
    4. chlorine

27. pH of gastric juice in the stomach is about

    1. 1.2
    2. 7
    3. 9
    4. 13

28. The number of water molecules in gypsum is

    1. ½
    2. 2
    3. 5
    4. 10

29. Which indicator is olfactory (smell-based)?

    1. litmus
    2. onion/vanilla
    3. phenolphthalein
    4. methyl orange

30. A base soluble in water is called

    1. an acid
    2. an alkali
    3. a salt
    4. a hydride

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