To determine the boiling point of water.MATERIALS REQUIREDDistilled water, boiling tube, rubber CORK with two bores, delivery tube, clamp stand, pieces of pumice stone/ porcelain pieces, beaker, thermometer, burner.THEORYH20 exists in three different physical states-solid ice, liquid water and water VAPOUR. In the liquid state, the forces of interaction are less and therefore, water exists as a liquid at ROOM temperature. The boiling point of water is 100 °C, i.e. the vapour pressure of water becomes equal to atmospheric pressure at 100 °C at sea level.PROCEDURETake about 50 ml distilled water in a boiling tube, and add few pieces of pumice stone/porcelain to it.Fix a cork with two bores in the mouth of the boiling tube and fix a thermometer in one bore and delivery tube in the other. Clamp the tube to the stand.Place a beaker below the open end of the delivery tube to collect condensed water.Heat the boiling tube by PREFERABLY rotating the flame for uniform heating.Note the temperature (t1) when water starts boiling.Heat CONTINUOUSLY till the temperature becomes constant, and water keeps on boiling. Note this temperature (t2)Record your observations in the table.OBSERVATIONSObservation TableMean value of temperatures = t1+t22Boiling point of water = ……………..°C.RESULTThe boiling poin of water = ……….. °CPRECAUTIONSUse distilled water only. Impure water and hard water have boiling point greater than 100°C.The bulb of the thermometer should be slightly above the liquid. Add porcelain pieces before heating to avoid bumping.Heat water by rotating the flame.Note the temperature by keeping the eyes in line with the level of mercury.