2. Acids, Bases and Salts

*नोट: यह सेक्शन रिवीजन के लिए है। अपना ज्ञान परखने के लिए ऊपर दिए गए क्विज़ में भाग लें।

1. Which of the following is a natural indicator?
   A) Phenolphthalein  |  B) Methyl orange  |  C) Litmus  |  D) All of the above
2. Which acid is produced in our stomach?
   A) H2SO4  |  B) HNO3  |  C) HCl  |  D) CH3COOH
3. Which natural acid is found in tomatoes?
   A) Acetic acid  |  B) Citric acid  |  C) Oxalic acid  |  D) Tartaric acid
4. Which acid is present in an ant's sting?
   A) Methanoic acid  |  B) Lactic acid  |  C) Oxalic acid  |  D) Citric acid
5. What is the pH value of acid rain?
   A) More than 7  |  B) Less than 5.6  |  C) 14  |  D) 10
6. What is the pH of pure water?
   A) 1  |  B) 7  |  C) 10  |  D) 14
7. What is used for the treatment of indigestion?
   A) Antibiotic  |  B) Antacid  |  C) Analgesic  |  D) Antiseptic
8. What is the chemical formula of Bleaching Powder?
   A) CaO  |  B) Ca(OH)2  |  C) CaOCl2  |  D) CaCO3
9. What is the correct formula of Washing Soda?
   A) NaHCO3  |  B) Na2CO3.10H2O  |  C) NaOH  |  D) NaCl
10. Plaster of Paris (POP) hardens to form:
    A) Limestone  |  B) Gypsum  |  C) Salt  |  D) Clay
11. Tooth decay starts when the pH of the mouth is:
    A) Higher than 7  |  B) Lower than 5.5  |  C) 8  |  D) 14
12. What is the chemical name of common salt?
    A) Sodium carbonate  |  B) Sodium chloride  |  C) Sodium hydroxide  |  D) Calcium chloride
13. Which acid is found in Vinegar?
    A) Lactic acid  |  B) Acetic acid  |  C) Citric acid  |  D) Oxalic acid
14. What is the chemical formula of Gypsum?
    A) CaSO4.1/2H2O  |  B) CaSO4.2H2O  |  C) CaSO4.5H2O  |  D) CaSO4.10H2O
15. What is the approximate pH of lemon juice?
    A) 2.2  |  B) 7.0  |  C) 10.0  |  D) 14.0
16. What is the nature of metallic oxides?
    A) Acidic  |  B) Basic  |  C) Neutral  |  D) None of these
17. How do acids taste?
    A) Sweet  |  B) Bitter  |  C) Sour  |  D) Salty
18. Bases turn red litmus paper to:
    A) Yellow  |  B) Blue  |  C) Green  |  D) Colorless
19. What is formed as a result of the reaction between an acid and a base?
    A) Only salt  |  B) Salt and Water  |  C) Only gas  |  D) None of these
20. What is the pH value of a neutral solution?
    A) 0  |  B) 14  |  C) 7  |  D) 1
21. Which gas is evolved when acids react with metals?
    A) Oxygen  |  B) Carbon dioxide  |  C) Hydrogen  |  D) Nitrogen
22. What is the range of the pH scale?
    A) 1 to 10  |  B) 0 to 14  |  C) 1 to 7  |  D) 0 to 100
23. Milk of Magnesia [Mg(OH)2] is used as an:
    A) Acid  |  B) Antacid  |  C) Salt  |  D) Catalyst
24. By what name is Sodium Hydroxide (NaOH) known?
    A) Caustic Soda  |  B) Baking Soda  |  C) Washing Soda  |  D) Blue Vitriol
25. What is the color of litmus solution when it is neither acidic nor basic?
    A) Red  |  B) Blue  |  C) Purple  |  D) Yellow
26. What is the nature of non-metallic oxides?
    A) Basic  |  B) Acidic  |  C) Neutral  |  D) Amphoteric
27. What is produced in a neutralization reaction?
    A) Acid + Base  |  B) Salt + Water  |  C) Gas + Water  |  D) Only salt
28. In the process of dilution, the concentration of H3O+ ions per unit volume:
    A) Increases  |  B) Decreases  |  C) Remains constant  |  D) Becomes zero
29. Which products are obtained from the Chlor-alkali process?
    A) Cl2 and NaOH  |  B) H2 and Cl2  |  C) NaOH, Cl2 and H2  |  D) NaCl and H2O
30. What is the chemical formula of Baking Soda?
    A) Na2CO3  |  B) NaHCO3  |  C) NaOH  |  D) KOH
31. The loss of water molecules by washing soda when exposed to air is called:
    A) Dehydration  |  B) Efflorescence  |  C) Precipitation  |  D) Combination
32. At what pH value does tooth enamel start to corrode?
    A) pH < 5.5  |  B) pH > 7  |  C) pH = 14  |  D) pH = 10
33. Acids produce which ions when dissolved in water?
    A) OH- ions  |  B) H+ or H3O+ ions  |  C) Cl- ions  |  D) Na+ ions
34. Bases produce which ions when dissolved in water?
    A) H+ ions  |  B) OH- ions  |  C) O2- ions  |  D) SO4- ions
35. What is the natural source of Citric acid?
    A) Tamarind  |  B) Curd  |  C) Orange or Lemon  |  D) Tomato
36. What is the chemical name of Plaster of Paris (POP)?
    A) Calcium sulphate dihydrate  |  B) Calcium sulphate hemihydrate  |  C) Calcium carbonate  |  D) Sodium sulphate
37. What is used in soda-acid fire extinguishers?
    A) Na2CO3  |  B) NaHCO3  |  C) NaCl  |  D) NaOH
38. Water of crystallization is found in:
    A) Washing soda and Gypsum  |  B) Baking soda  |  C) Quick lime  |  D) Common salt
39. The strength of acids and bases depends on:
    A) Their weight  |  B) Number of H+ and OH- ions produced  |  C) Color  |  D) Price
40. Bases that are soluble in water are called:
    A) Acids  |  B) Alkalis  |  C) Salts  |  D) Indicators
41. What is the ratio of concentrated HCl and HNO3 in Aqua Regia?
    A) 1:3  |  B) 3:1  |  C) 1:1  |  D) 2:3
42. How is the gas evolved during the reaction of dilute sulphuric acid with zinc granules tested?
    A) By moisture  |  B) By bringing a burning candle (Pop sound)  |  C) By color  |  D) By smell
43. Why does dry HCl gas not change the color of dry litmus paper?
    A) It is not an acid  |  B) Due to the absence of H+ ions  |  C) Litmus paper is faulty  |  D) Gas is cold
44. Who developed the pH scale to measure the concentration of hydrogen ions (H+)?
    A) Dalton  |  B) Sorensen  |  C) Lavoisier  |  D) Newton
45. Metal carbonates react with acids to produce which gas?
    A) H2  |  B) CO2  |  C) O2  |  D) N2
46. What is the name of the industrial process for manufacturing Caustic Soda (NaOH)?
    A) Solvay process  |  B) Chlor-alkali process  |  C) Haber process  |  D) Contact process
47. What do doctors use to support fractured bones in the right position?
    A) Gypsum  |  B) Plaster of Paris  |  C) Lime  |  D) Washing soda
48. What should be the pH of the soil for the healthy growth of plants?
    A) Highly acidic  |  B) Highly alkaline  |  C) A specific range (near neutral)  |  D) Zero
49. Which acid is found in Tamarind?
    A) Citric acid  |  B) Tartaric acid  |  C) Methanoic acid  |  D) Lactic acid
50. Which mild base is effective for treating a bee sting?
    A) Lemon juice  |  B) Baking Soda  |  C) Vinegar  |  D) Salt
51. On the pH scale, moving from 7 to 14 indicates an increase in the concentration of:
    A) H+ ions  |  B) OH- ions  |  C) H3O+ ions  |  D) Cl- ions
52. What is mixed with baking soda to make baking powder?
    A) Sulphuric acid  |  B) A mild edible acid (like tartaric acid)  |  C) NaOH  |  D) HCl
53. What is used for softening hard water?
    A) NaCl  |  B) Na2CO3  |  C) NaHCO3  |  D) CaSO4
54. What is the approximate pH value of gastric juice?
    A) 1.2  |  B) 7.4  |  C) 10  |  D) 14
55. What is the pH value of blood?
    A) 6.5  |  B) 7.4  |  C) 8.5  |  D) 4.0
56. The natural remedy for the pain caused by the stinging hair of nettle leaves is:
    A) Neem leaf  |  B) Dock plant leaf  |  C) Tulsi  |  D) Soil
57. At what temperature is Gypsum heated to turn into POP?
    A) 100°C (373 K)  |  B) 200°C  |  C) 50°C  |  D) 0°C
58. Why are copper vessels cleaned with sour substances?
    A) To bleach the color  |  B) To neutralize the basic copper carbonate layer  |  C) To increase shine  |  D) None of these
59. What is the correct formula for Sodium Zincate?
    A) NaZnO2  |  B) Na2ZnO2  |  C) NaZn(OH)4  |  D) Na2Zn
60. While diluting an acid, it is recommended that the acid should be added to water because the process is:
    A) Very slow  |  B) Highly Exothermic  |  C) Endothermic  |  D) Safe