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The solution containing the mixture is taken in a china dish and heated gently. Gradually the solvent evaporates and the solution containing the dissolved solute becomes thicker. The semi-solid mass left on the china dish is slowly heated to dryness. Fig: 1.3 - Evaporation of a soluti..

The solution containing the suspended impurities is made to pass through the porous membrane such as filter paper, filter cloth etc. The solvent or solution containing dissolved substances passes through the porous membrane, which is called filtrate. The insoluble solid suspended particles that re..

The mixture to be separated is taken in a suitable solvent and the solution is poured on the top of the column of the adsorbent. It is allowed to pass slowly through it and as it passes through the column the different constituents of the mixture get adsorbed to different extent, forming bands in ..

Mining of Sulphur - Frasch Process A Frasch pump consisting of a set of three concentric pipes is sunk deep into the sulphur bed Super heated water at 170 0 C under pressure is pumped in through the outermost pipe Sulphur in the sulphur bed melts due to its contact with hot ..

The aqueous solution of the compound (to be extracted) is taken in a separating funnel. A small quantity of a suitable organic solvent is added to this. The separating funnel is stoppered and the contents are shaken for some time. The funnel is then allowed to stand undisturbed on a tripod stand f..

The mixture is taken in a china dish covered with a wire guaze. An inverted glass funnel is placed on this to collect the vapors. Sometimes a perforated asbestos sheet is placed between the china dish and the funnel. The stem of the funnel is plugged with a little cotton and the sides are kept coo..

Crude petroleum is pumped into the furnace where it is heated to a temperature of about 400 o C. Petroleum is converted to vapours in the furnace. The vapours of petroleum are fed into the fractionating column from the bottom. As the vapours enter the column, they rise up and gradually get ..

Compression Pump: Mixture of N 2 and H 2 in the ratio 1:3 is compressed to 152000-684000 mm of Hg pressure. The compressed mixture of N 2 and H 2 is passed over heated catalyst. Ammonia is formed. Heat exchange takes place between residual N 2 and H 2 and the incoming unreacted N 2 and H 2 ..

The metal to be refined is heated above its boiling point Impurities do not vapourise Pure metal vapourises and is condensed Impurities are left behin..

Hydraulic Washing Powdered ore is spread over a sloping wooden platform which vibrates continuously. Small wedge shaped obstacles are fixed on the platform. A strong jet of water is passed over the platform. Lighter gangue particles are washed away while the heavier ore particles are left behi..