Separation Of Substances

Threshing and filtration

Handpicking

True

By threshing farmer can separate grain seeds from bundles of stalk.

Winnowing

Handpicking

Threshing

True

Sieving

True

Sedimentation

The process in which water is removed when heavier component of mixture settles, it is called decantation.

Decantation.

Filtration

The process of conversion of water into its vapour is called evaporation.

True

True

Sand can be separated from water by sedimentation.

True

By evaporation

True

Condensation.

TRUE

No

Saturated

On heating the water

A solution is prepared by dissolving a substance in a liquid

True

Saturated solution

Sedimentation.

Sedimentation, decantation.

b

Decantation

Handpicking

Decantation

C

Handpicking

False

No

Hand picking is the method of separating easily identifiable material from a mixture. The components of the heterogeneous mixture can be separately identified from each other. And they can be separated from each other by using hand picking.

Hand picking is the method of separating easily identifiable material from a mixture. The components of the heterogeneous mixture can be separately identified from each other. And they can be separated from each other by using hand picking.

Hand picking is the method of separating easily identifiable material from a mixture. The components of the heterogeneous mixture can be separately identified from each other. And they can be separated from each other by using hand picking.

Chaff is a mixture of dried leaves, stem and seed covering separated by winnowing or threshing.

Sieve is an instrument with a meshed or perforated bottom, used for separating coarse from fine parts of loose matter, for straining liquids, etc.,especially one with a circular frame and fine meshes or perforations. The process of separation impurities of different size using sieve is called sieving.

The fine flour particles to pass through the holes of the sieve while the bigger impurities remain on the sieve.

By sieving salt will go down from sieve while sugar particle will remain in sieve.

Winnowing is used to separate heavier and lighter components of a mixture by wind or by blowing air.

Tea strainer is a type of sieve, which is used to separate tea leaves from water.

The process that is used to separate grain from stalks etc. is threshing. In this process, the stalks are beaten to free the grain seeds. Threshing is done with the help of hand ,bullocks or machines.

Threshing is the process of loosening the edible part of cereal grain (or other crop) from the scaly, inedible chaff that surrounds it. It is the step in grain preparation after harvesting and before winnowing, which separates the loosened chaff from the grain. Threshing does not remove the bran from the grain.

Ans: b.

Milk can be separated into cream which is a useful thing. It can be used as fat. The remaining mixture is also useful. Jaggery is a component of sugarcane juice, which is a useful thing.

Jaggery is a component of sugarcane juice, which is a useful thing.The benefits of Jaggery include its ability to cleanse your body, act as a digestive agent, sweeten your food in a healthy manner, and provide good amounts of minerals.

Ans: c.

Churning process is used to separate the butter from the milk. Moving the milk or curd continuously with skimmers produces butter .This process is called churning.

Ans: b.

Ans: b.

Ans: a.

Magnetic separation is used to separate the mixture where one substance has magnetic properties. Here in the mixture of Iron and Sulphur, Iron has magnetic properties so it will attract to magnet.

Ans: a.

When the heavier component in a mixture settles after water is added to it, the process is called sedimentation. The liquid above sediments in the process of sedimentation is called supernatant.

Decantation is a process for the separation of mixtures, by removing a layer of liquid, generally one from which a precipitate has settled. The purpose may be either to produce a clean decant, or to remove undesired liquid from the precipitate (or other layers)

Evaporation is the process of a substance in a liquid state changing to a gaseous state due to an increase in temperature and/or pressure.

Condensation is the change of the physical state of matter from gas phase into liquid phase, and is the reverse of evaporation.

Ans: a.

When sea water is allowed to stand in shallow pits, water gets heated by sunlight and changes into water vapour by the process of evaporation leaving behind impure solid salts. Now, the lumps of impure common salt are crushed to get powdered salt. The powdered common salt is dissolved in water to prepare a solution. Now the solution of common salt is filtered to remove insoluble impurities. The clear solution is evaporated by heating to remove the water content to obtain a concentrated solution of common salt. The hot and concentrated solution is allowed to cool. On cooling, crystallization takes place and crystals of pure common salt are obtained.

Ans: b.

Ans: d.

Ans: b.

Ans: a.

Loading is the process of faster sedimentation by suspending alum to a liquid.

We need to separate different components of a mixture to obtain the useful component (removing tea leaves after making tea),to remove harmful component(rice grains after separating husk) and to remove impurities for getting pure substance(salt from sea water).

Pure substances are defined as substances that are made of only one type of atom or only one type of molecule .Elements and compounds are pure substances.

Impure substances may be a mixtures of elements, mixtures of compounds, or mixtures of elements and compounds.

Purity is defined as the quality or state of being pure.

Ans: b.

Mixtures in which particles of the substances present can be seen easily are called heterogeneous mixtures. For example, water in oil, dust in air.

Take a beaker (100 ml) half filled with given sample of water. Stir the water thoroughly. Now keep the beaker undisturbed for some time. Sand gets settled down at the bottom of the beaker. After sometime water can be separated by decantation process and sand is left in beaker.

For making paneer, a few drops of lemon juice are added to milk as it boils. This gives a mixture of particles of solid paneer and a liquid. The paneer is then separated by filtering the mixture through a fine cloth or a strainer.

Ans: a.

Ans: a.

Ans: a.

Ans: b.

Ans: b.

Ans: d.

Ans: b.

Solute and solvent are decided on the basis of concentration. The substance whose concentration is less is the solute and vice versa. So in this case sugar is the solute.

Solubility of substance depends on temperature and pressure.

A saturated solution is a chemical solution containing the maximum concentration of a solute dissolved in the solvent.

Water is often called a universal solvent because many substances dissolve in it. However, no one substance can dissolve every solute

Substances in which you can dissolve more solute is called Unsaturated Solution.For example An unsaturated tea and sugar solution would be one into which you could add more sugar and have the sugar still dissolve.

The substance that is being dissolved is called a solute and the substance that does the dissolving is called the solvent. water is dissolving salt in it. So, it is solvent.

The substance that is being dissolved is called a solute and the substance that does the dissolving is called the solvent. Salt is dissolved in ocean water. So, it is solute.

A solution that contains more solute than the solvent can dissolve is known as a supersaturated solution. Solubility increases when the temperature of the solvent is increased.