IS MATTER AROUND US PURE
Keys words
1. Pure substance
2.Element
3.Compounds
4.Mixture
5.Solution
6.Suspension
7.Colloidal solution
Pure substance consists of a single type of
particles.
It represents a single substance.
ELEMENT
Robert Boyle was the first scientist to
use the term element in 1661.
, Antoine Laurent Lavoisier, a French
chemist was the first to establish an
experimentally useful definition of the
element. According to him-
A substance which can neither be broken
down into simpler substances nor
formed from two or more simple
substances by know physical chemical
process.
EXAMPLE: - hydrogen, oxygen, nitrogen
etc.
*Elements are regarded as the building
block of the universe.
*Nitrogen is the most abundant element
in the atmosphere.
*Oxygen is the most abundant element
on the earth crust.
*There are 118 elements.
*92 are natural and remaining are
artificial.
*Mercury is the only metal liquid at room
temperature.
* Bromine is the only non -metal liquid at
room temperature.
e m e n ts
metals
non-
metals
, metalloids
e
Properties of metals:-
Matter have luster and can be polished.
They are good conductors of electricity
and heat.
They are ductile, i.e. can be drawn into
wires.
Metals have high densities.
Metals are hard and have high melting and
boiling point.
Examples:-sodium, potassium, zinc,
copper, silver, gold, aluminum.
Properties of non-metals:-
Non- metals have no luster
They are poor conductors of heat and
electricity.
They are soft and brittle.
They have lower densities.
Non-metals have low melting and boiling
point.
Keys words
1. Pure substance
2.Element
3.Compounds
4.Mixture
5.Solution
6.Suspension
7.Colloidal solution
Pure substance consists of a single type of
particles.
It represents a single substance.
ELEMENT
Robert Boyle was the first scientist to
use the term element in 1661.
, Antoine Laurent Lavoisier, a French
chemist was the first to establish an
experimentally useful definition of the
element. According to him-
A substance which can neither be broken
down into simpler substances nor
formed from two or more simple
substances by know physical chemical
process.
EXAMPLE: - hydrogen, oxygen, nitrogen
etc.
*Elements are regarded as the building
block of the universe.
*Nitrogen is the most abundant element
in the atmosphere.
*Oxygen is the most abundant element
on the earth crust.
*There are 118 elements.
*92 are natural and remaining are
artificial.
*Mercury is the only metal liquid at room
temperature.
* Bromine is the only non -metal liquid at
room temperature.
e m e n ts
metals
non-
metals
, metalloids
e
Properties of metals:-
Matter have luster and can be polished.
They are good conductors of electricity
and heat.
They are ductile, i.e. can be drawn into
wires.
Metals have high densities.
Metals are hard and have high melting and
boiling point.
Examples:-sodium, potassium, zinc,
copper, silver, gold, aluminum.
Properties of non-metals:-
Non- metals have no luster
They are poor conductors of heat and
electricity.
They are soft and brittle.
They have lower densities.
Non-metals have low melting and boiling
point.
