Mark ‘T’ if the statement is true and ‘F’ if it is false. (i) Nitric acid turns red litmus blue. (T/F) (ii) Sodium hydroxide turns blue litmus red. (T/F) (iii) Sodium hydroxide and hydrochloric acid neutralise each other and form salt and water. (T/F) (iv) Indicator is a substance which shows different colours in acidic and basic solutions. (T/F) (v) Tooth decay is caused by the presence of a base. (T/F)
ScienceClass 7CBSEAnswered 27 Mar 2026
Answer
Solution:
- i) False
- ii) False
iii) True
- iv) True
- v) False
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