Ch10 Chapter Exercise Answers

Chapter exercise                                                                                                                p.128

Concept Checking

1.     False

Acid-alkali (àpH paper / Universal) indicators can be used to show the degree of acidity or alkalinity of a solution.

3.     True

5.     False

        Unpolluted rainwater is neutral (àslightly acidic).

6.     True

Multiple Choice

7.     B

8.     D

9.     B

10.   D

Short-answer Questions

12.   (a)    Marigold and choi sum. They do not show different colours in acids and alkalis.

        (b)    Yellow

        (c)    Pink

13.   (a)    Magnesium / zinc / iron (Any one)

        (b)    Hydrogen

        (c)    Test the gas with a burning splint. If the gas burns with a ‘pop’ sound, it is hydrogen.

        (d)   There would be no reaction.