Q61 of 270 Page 82

How could the person change his eating habits to lessen chances of suffering from tooth decay?

The best way to prevent this is to clean the mouth after eating every meal. Using toothpastes, which are generally basic, for cleaning the teeth can neutralize the excess acid and prevent tooth decay.

More from this chapter

All 270 →
61 Explain why the pH in a person's mouth becomes lower after each meal. 61 What damage could be caused while the pH is low? 62 A group of students measured the pH of some substances they found in their homes. Their results are given in the following table:


(a) What would the students have used to measure the pH?


(b) Which solution is the most acidic?


(c) Which solution is the most alkaline?


(d) Which solutions are neutral?


(e) Which solution can be used to treat wasp stings?


(f) Which solution can be used to treat bee stings?

 63 Hydrochloric acid reacts with a metal X to form a gas Y which burns with a 'pop' sound. Sodium hydroxide solution also reacts with the same metal X (on heating) to form the same gas Y.

(a) Name X and Y


(b) Write the chemical equation of the reaction of metal X with


(i) hydrochloric acid, and


(ii) sodium hydroxide solution.