Extra Question:
Que: What is the testy for acids and bases using litmus paper?
Ans: Acids turn blue litmus paper red while bases turn red litmus paper blue.
Que: What name is given to those to those substances which do not change the color of either red or blue litums paper?
Ans: The solutions or substances which do not change the color of either red or blue litmus paper are meutral.
Que: Write the name of two indicators which occur naturally?
Ans:
- Turmeric
- China rose
Que: Name the acid present in lemon juice and tomato?
Ans: Citric acid in lemon juice and oxalic acid in tomato.
Que: Name a substance which is used to cure the discomfort caused by indigestion due to over eating?
Ans: Milk of magnesia which contains magnesium hydroxide is used to neutralise the effect of excessive acid in stomach.
Que: Is time water an acidic or basic solution?
Ans: Lime water is basic solution.
Que: Name the reaction when an acid is mixed with base.
Ans: Neutralisation reaction.
Que: Which acid is injected into our body an ant sting that causes pain?
Ans: The acid is formic acid which is injected into the skin of a person when an ant bites.
Que: Write twi basic substances which we use in our daily life?
Ans:
- baking soda
- Soap or detergent
Que: Name one acid which is responsible for acid rain.
Ans: Carbonic acid.
Que: Why are sodium bicarbonate and lemon used during indigestion?
Ans: Sodium bicarbonate neutralises the acidity in the stomach. Hence, it is used during indigestion. Lemon contains acid. It reacts with undigested food and suffers it.
Que: How lime water is prepared in the laboratory?
Ans: To prepare lime water, disslove some lime in water in a bottle. Stir the solution and keep it for sometime. pour a little from the top. This is lime water.
Que: Which is an acid - base indicator?
Ans: Turmeric.
