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Boyles Law

Boyle's Law, in Physics, states that if a given quantity of any gas be subjected to any variation in volume while its temperature is kept constant, the pressure will vary in such a way that the product of volume and pressure remains a constant. Thus if the volume v of a certain mass of hydrogen be 40 cubic centimetres, when its pressure p is equal to that of 76 cms. of mercury, then if the temperature is kept constant throughout vp = 76 x 40 = 3040 always. As a matter of fact the law is not perfectly obeyed by any gas, though the approximation becomes closer and closer as the temperature of the gas is taken farther from its point of liquefaction. Thus hydrogen and oxygen, which at ordinary temperatures are both far from their points of liquefaction, follow Boyle's law closely. Carbon dioxide, which is more readily liquefied, shows an evident discrepancy at ordinary temperature.