What are things made of?

Q What are the methods used to separate mixtures?A: These methods are known as physical methods. The methods are

Magnetic attraction: We can separate magnetic materials like iron and steel by passing a strong magnet from scrap metal.

Decanting: If the solid sinks, you can pour the liquid off the top.Sieve: A sieve works by holding the large solid pieces in the sieve so the liquid can escape through the holes. Different sieves have different size of holes. You

can separate large and small particles. Filtration: Filter paper has very small holes. It is like mini sieve. Liquids can pass

through but tiny particles of solid are left behind. It is used to separate insoluble solids from a liquid, like sand.

Evaporation: It is used to separate dissolved solids from a solution. During evaporation, the water changes into steam, leaving solute like salt as residue.

Chromatography: Chromatography separates coloured components in a mixture. It works on the fact that the different components of a liquid mixture

travel at different rates on paper because some components are more attracted to paper than others.

Distillation: Distillation separates a liquid from a solution. It involves two processes called boiling and condensation. The pure water is called distilled

water. The steam from boiling water is condensed and into water.Fractional distillation: It is used to separate a mixture of 2 or more liquids that

have different boiling points.

Magnetic attraction: We can separate magnetic materials like iron and steel by passing a strong magnet from scrap metal.

Decanting: If the solid sinks, you can pour the liquid off the top.

Sieve: A sieve works by holding the large solid pieces in the sieve so the liquid can escape through the holes. Different sieves have different size of holes. You can separate large and small particles.

Filtration: Filter paper has very small holes. It is like mini sieve. Liquids can pass through but tiny particles of solid are left behind. It is used to separate insoluble solids from a liquid, like sand.

Evaporation: It is used to separate dissolved solids from a solution. During evaporation, the water changes into steam, leaving solute like salt as residue.

Chromatography: Chromatography separates coloured components in a mixture. It works on the fact that the different components of a liquid mixture travel at different rates on paper because some components

are more attracted to paper than others.

Distillation: Distillation separates a liquid from a solution. It involves two processes called boiling and condensation. The pure water is called distilled water. The steam from boiling water is condensed and into water.

.

Fractional distillation: It is used to separate a mixture of 2 or more liquids that have different boiling points.

Q Why do we need to separate the substances from mixtures?A: Some mixtures contain useful substances. So we need to separate them before use.