Determining Solubility of Air in Water

Determining Solubility of Air in Water. Assemble an apparatus (Fig. 47) so that the end of the tube does not emerge from the stopper. The volume of the flask should be 250-300 ml. Check the tightness of the apparatus. Measure the volume of the flask up to the stopper. 

Pour about 350 ml of distilled water into a flask with a volume of 0.5-1 litre and saturate it with air by shaking it. Fill the flask of the apparatus and the gas-discharge tube with the water saturated with air. Close the flask, making sure that not a single air bubble remains in the flask and in the tube. Put a test tube filled with water onto the free end of the gas-discharge tube immersed in a bath with water and fasten it in a stand (the test tube and the stand are not shown in 

Adjust the pressure of the gas in the test tube to atmospheric, mark the level of the water with a rubber band, and determine the volume of the evolved gas with a small measuring glass. Enter the cesults in your laboratory notebook using Form 13. 

Volume of water In flask, ml Volume of evolved gas under given conditions, ml Atmospheric pressure of gas, mmHg Temperature, Water vapour pressure, mmHg 

Calculate the volume of dry air that was dissolved in the water Tinder the conditions of the experiment. How does the solubility of gases change with a change in the pressure What was the composition of the gas that evolved from the water  

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