C11 Chemical Reaction 2

All chemical changes take place very fast.

• True

• False

The red litmus paper turns blue. This shows that the solution is

• acidic

• alkaline

• neutral

The number of atoms in reactants is more than that in products.

• True

• False

A ripe banana is slightly acidic. Suggest the pH of this food. [Write the numerical value of the pH]

(a)  

Which of these are not indicators?

• methyl orange

• phenol blue

• bromomethyl blue

• litmus paper

Boiled red cabbage can be used as natural pH indicator.

• True

• False

The picture shows the colours of indicators as pH increases. Choose the statement that is false.

• I can identify acidic solutions easily using these indicators.

• I can identify neutral solutions easily using these indicators.

• I can identify alkaline solutions easier using litmus paper than methyl orange indicator.

Farmers add slaked lime to acidic soil which will then allow plants to grow better. This is a ... process.

• combustion

• oxidation

• neutralisation

• rusting

Universal indicator is used to test the pH of lemon. The pH of lemon is ....

• 3

• 6

• 9

• 12

A tablespoon of antacid is to a cup of tap water. What happens to the pH of the water?

• pH does not change

• pH increases

• pH decreases