Pure substances possess
Variable melting points and boiling points
Nonuniform
Variable properties
Fixed melting points and boiling points
Impurities like bran, worms, tiny insects from flour can be separated by
winnowing
handpicking
sieving
filtration
Which one of the following is not an example of a separation?
Tea strainer
Surgical mask
Boiling an egg
Fishing net
Winnowing is useful only when
Two solids have different melting points
Two solids have different boiling points
Two solids have different magnetic properties
Two solids have different weights
Which type of particles can be separated by winnowing?
Heavier particles
Lighter particles
Both (1) and (2)
None of the above
A mixture is a / an
Pure substance
Impure substance
Some are pure and others are impure
None
Identify which method of separation is used?
Sedimentation
Filtration
Decantation
Which of the following mixtures will be the most difficult to separate ?
Iron filings + sand
Sand + water
Saw dust + stones
Nitrogen + hydrogen
The process by which a solid changes directly into gas is called
Sublimation
Condensation
....... and ...... are the basic processes involved in the water cycle.
Filtration and evaporation
Sedimentation and condensation
Evaporation and condensation
Sedimentation and filtration
