CBSE – 9th Standard Science

• A mixture contains more than one substance mixed in any proportion.
• A pure substance consists of a single type of particles.
• A solution has a solvent and a solute as its components.
• A Solution is a homogeneous mixture of two or more substances.
• Air is a homogeneous mixture and can be separated into its components.
• Brass is mixture of approximately 30% of zinc and 70% of copper
• By some separation techniques mixtures can be separated into pure substances

• Suspension is a heterogeneous mixture here the particles of a suspension can be seen by the naked eye
• A colloid is also heterogeneous mixture but the size of particles of a colloid is too small to be individually seen by naked eyes
• Collid do not settle down when left undisturbed.
• The concentration of a solution is the amount of solute present in a given amount of solution, or the amount of solute dissolved in a given mass or volume of solvent.

    Separating the Components of a Mixture

• SEPARATE COLOURED COMPONENT (DYE) FROM BLUE/ BLACK INK

         EVAPORATION

                      

 

• SEPARATE CREAM FROM MILK BY CENTRIFUGATION

 

• SEPARATE A MIXTURE OF TWO IMMISCIBLE LIQUIDS

SEPARATING FUNNEL          

• SEPARATE A MIXTURE OF SALT AND AMMONIUM CHLORIDE

         SUBLIMATION

• SEPARATE THE DYE IN BLACK INK BY CHROMATOGRAPHY

This process of separation of components of a mixture is known as chromatography.

• SEPARATE A MIXTURE OF TWO MISCIBLE LIQUIDS

         Distillation used for the separation of components of a mixture containing two miscible liquids that boil                    without decomposition and have sufficient difference in their boiling points.

• SEPARATE DIFFERENT GASES FROM AIR

Air is a homogeneous mixture and can be separated into its components by fractional distillation.

• SEPARATE PURE COPPER SULPHATE FROM AN IMPURE SAMPLE

PURIFICATION OF SOLIDS BY CRYSTALLIZATION

 PURE SUBSTANCES AND MIXTURES

 

• Elements or compounds just mix together to form a mixture and no new compound is formed. A mixture has a variable composition

• Elements react to form new compounds. The composition of each new substance is always fixed.

• Elements cannot be broken down into simpler substances.

• Sugar, water, methane and salt are some of the examples of compounds

• Properties of a compound are different from its constituent elements