Chapter 5 Form 2 Science

Water is a ____________________________ .

• mixture

• atom

• compound

• solid

Water molecule is made of ___________ of hydrogen and __________________ atom of oxygen.

• one , two

• three , two

• two , one

• two , two

Sublimation is a process of changes in the state of matter from ___________________________________________

• gas to solid

• solid to liquid

• liquid to gas

• gas to liquid

These two processes absorbs heat energy during the changes in the state of matter.

• freezing and evaporation

• evaporation and condensation

• boiling and melting

• freezing and condensation

During electrolysis the ___________________ gas is produced at the anode

• oxygen

• hydrogen

The impurities such salt when added to water will _______________ the freezing point of water.

• increase

• remain the same

• decrease

Evaporation only occurs on the ___________________ of water

• bottom

• surface

• boiling point

Tick the correct physical appearance of pure water.

• Colourless

• Speechless

• Tasteless

• Odorless

When we add salt into pure water, the boiling point of the solution will

• be more than the pure water boiling point.

• be less than the pure water boiling point.

• same as the pure water boiling point.

Insects like daddy longlegs can move on the surface of the water because of

• water has higher density than insects.

• water is heavier than the insects.

• water has high surface tension.