A compound has
Only one kind of atom
Only one kind of element
A mixture of elements and molecules
Only one kind of molecules
Which of the following mixtures will be the most difficult to separate ?
Iron filings + sand
Sand + water
Saw dust + stones
Nitrogen + hydrogen
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
A pure substance is made up of
Two or more kinds of molecules
Different types of molecules
None
From the following which one is not a mixture.
Alum
A platinum bangle
A gold chain of 22 ct.
Blank ink
A few coloured glass pieces that are big in size are mixed with sugar. The easiest way to separate them is
Heat the mixture
Add the mixture to water
Handpick the glass pieces
Handpick the sugar particles
To separate ammonium chloride from common salt, we use
Filtration
Sedimentation
Sieving
Sublimation
We separate mixtures to
Remove unwanted components
To get pure substances
Both the above
None of these
The following property is used to find the purity of a substance
Specific gravity
Volume
Temperature
Mass
Identify the mixture from the following
Carbon dioxide
Iron
Hydrogen
Air
