Is Matter Around Us Pure? Class 9 PPT

 Page 1


CHAPTER - 2
IS MATTER AROUND 
US PURE?
Page 2


CHAPTER - 2
IS MATTER AROUND 
US PURE?
PURE SUBSTANCES
• Pure substances are elements or compounds.
• They are made up of only one kind of entity.
• They cannot be broken down into simpler 
entities by chemical or physical methods.
• They have a fixed composition.
• Example: Diamond, carbon dioxide.
• Matter can be classified into two types of 
substances – Pure substances and Mixtures
Page 3


CHAPTER - 2
IS MATTER AROUND 
US PURE?
PURE SUBSTANCES
• Pure substances are elements or compounds.
• They are made up of only one kind of entity.
• They cannot be broken down into simpler 
entities by chemical or physical methods.
• They have a fixed composition.
• Example: Diamond, carbon dioxide.
• Matter can be classified into two types of 
substances – Pure substances and Mixtures
Mixtures are formed by 
just mixing two or more 
pure substances 
(components) such that 
each substance retains its 
own chemical identity.
WHAT IS A 
MIXTURE?
Page 4


CHAPTER - 2
IS MATTER AROUND 
US PURE?
PURE SUBSTANCES
• Pure substances are elements or compounds.
• They are made up of only one kind of entity.
• They cannot be broken down into simpler 
entities by chemical or physical methods.
• They have a fixed composition.
• Example: Diamond, carbon dioxide.
• Matter can be classified into two types of 
substances – Pure substances and Mixtures
Mixtures are formed by 
just mixing two or more 
pure substances 
(components) such that 
each substance retains its 
own chemical identity.
WHAT IS A 
MIXTURE?
1. HOMOGENEOUS 
MIXTURE
• A mixture which has a 
uniform composition 
throughout is 
called a homogeneous 
mixture or solution.
• Examples: sugar in water, 
salt in water.
Page 5


CHAPTER - 2
IS MATTER AROUND 
US PURE?
PURE SUBSTANCES
• Pure substances are elements or compounds.
• They are made up of only one kind of entity.
• They cannot be broken down into simpler 
entities by chemical or physical methods.
• They have a fixed composition.
• Example: Diamond, carbon dioxide.
• Matter can be classified into two types of 
substances – Pure substances and Mixtures
Mixtures are formed by 
just mixing two or more 
pure substances 
(components) such that 
each substance retains its 
own chemical identity.
WHAT IS A 
MIXTURE?
1. HOMOGENEOUS 
MIXTURE
• A mixture which has a 
uniform composition 
throughout is 
called a homogeneous 
mixture or solution.
• Examples: sugar in water, 
salt in water.
2. HETEROGENEOUS 
MIXTURE
• A mixture which contains 
physically distinct parts and 
has a non-uniform 
composition is called 
a heterogeneous mixture.
• Examples: Mixture of 
sodium chloride (salt) and 
iron filings, sand and sugar.