Give reasons for the following statements: The filter paper made into a cone & placed in a funnel for filtering out the solid particles in a solid-liquid mixture, should be moistened before placing.

Give reasons for the following statements: Centrifugation can be used for separating an insoluble heavier solid, present in an insoluble solid-liquid mixture.

Give two examples for the following : Solid+ Liquid mixture

Give reasons for the following in one or two sentences. (i) Equal volumes of gases contain equal number of moles. (ii) A bottle of liquid ammonia should be cooled before opening the stopper.

Give one example for each of the following types of mixtures. (a) Solid-solid heterogeneous mixture (b) Solid-liquid heterogeneous mixture (c) Solid-liquid homogeneous mixture

For each of the following statements, say whether it describes a solid, a liquid or a gas. (a) Particles move about very quickly but do not leave the surface. (b) Particles are quite close together. ( c) Particles are far apart and move in all directions.

Consider the following statements and arrange in the order of true/false as given in the codes. S_1 :The addition of chlorine water drop wise to a solution of a bromide liberate free bromine, which colours the solution orange red. S_2 :Chlorine gas bleaches the filter paper moistened with yellow dyestuff, fluorescein. S_3 :Nitrogen gas is evolved when a solution of nitrate is boiled with zinc dust and sodium hydroxide solution.

Place the following systems in order of increasing randomnes: a. 1mol of a gas X b. 1mol of a solid X c. 1 mol of a liquid X

Which of the following statements are correct ? (i) When an animal hide, which has negatively charged particles , is soaked in tannin, which contains positively charged colloidal particles, mutual coagulation does not take place. (ii) Photographic films are prepared by coating an emulsion of the light sensitive silver bromide in gelatin over glass plates or celluloid films. (iii) Latex is a colloidal solution of rubber particles which are negatively charged. (iv) In Cottrell precipitator , the smoke , before it comes out from the chimney, is led through a chamber containing plates having a charge opposite to that carried by smoke particles. The particles on coming in contact with these plates acquire some charge and do not get precipitated .

The solid particles which remain on the filter paper are called and the liquid which passes through it is called…………….

A child wanted to separate the mixture of dyes constituting a sample of ink. He marked a line by the ink on the filter paper and placed the filter paper in a glass containing water as shown in figure. The filter paper was removed when the water moved near the top of the filter paper. (a) What would you expect to see, if the ink contains three different coloured components? (b) Name the technique used by the child. (c) Suggest one more application of this technique.