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
Pick out the liquid-in-gas type of mixture from the following.
Dissolved carbon dioxide in water
Droplets of water in air
Oxygen dissolved in water
All of the above
Which of the following mixtures will be the most difficult do separate ?
Iron fillings + sand
Sand + water
Saw dust + stones
Nitrogen + hydrogen
In a mixture , constituents exhibit :
similar properties
only those properties which are characteristic to the mixture
their own properties
no properties
A small boy mischievously mixed small pebbles into a bag of pulses. What method will you employ to separate the mixture ?
Magnetic separation
Crystallisation
Handpicking
Filtration
Mixtures in which components can be distingushed are called :
heterogeneous
homogenous
pure substances
solutions
The heterogeneous mixture of soot particles in air is a mixture of :
solid-in-solid
solid-in-gas
gas-in-solid
gas-in-gas
A coagulant is :
special chemical which helps small fine particles to settle down
which helps the substance to sublime
filtering agent
none of the above
Identify the compound from the following.
Carbon dioxide
Iron
Hydrogen
Air
We separate mixtures to :
remove unwanted components
to get pure substances
both the above