Ans: Acetic acid (CH3COOH)
Q42. What is the pH of pure water?
Ans: 7 (neutral)
Q43. What is the effect of pH on tooth decay?
Ans: Lower pH (<5.5) causes enamel to corrode, leading to tooth decay.
Q44. Which base is present in antacid tablets?
Ans: Magnesium hydroxide (Mg(OH)2)
Q45. Name one indicator used in acid-base titration.
Ans: Phenolphthalein
Q46. What is a universal indicator?
Ans: A mixture of indicators that shows different colors at different pH levels.
Q47. Define acidic and basic solutions.
Ans: Acidic: pH < 7, Basic: pH > 7
Q48. What is formed when acid reacts with metal?
Ans: Salt and hydrogen gas
Q49. Why are acids not stored in metal containers?
Ans: Because they react with metals to produce hydrogen gas.