6.3 Compounds

1. Compound can be separated ________.

• physically

• chemically

2. A compound can only be separated chemically by the process of _______________.

• photosynthesis

• electrolysis

• respiration

• combustion

3. Water consists of ___________ and __________.

• carbon dioxide

• oxygen

• carbon monoxide

• hydrogen

4. Hydrogen gas is connected to the negative electrode which is called ______________

• anode

• cathode

5. Oxygen gas is connected to the positive electrode which is called ________________.

• anode

• cathode

6. Give the ratio of oxygen to hydrogen in water.

• 2:1

• 1:2

• 2:2

• 1:1

7. State the name of the acid that mixed with water during the process of electrolysis.

• nitrate acid

• sulphuric acid

8. Physical change form a new substance.

• YES

• NO

9. Photosynthesis is an example of chemical change.

• YES

• NO

10. How to determine the presence of oxygen in electrolysis ?

• Lime water turns cloudy.

• Lights up the glowing wooden splinter.

• Extinguishes the wooden splinter.

• The blue litmus paper turns red.