GAS LAWS DESCRIBE THE BEHAVIOR OF GASES

Notice in the example involving the piston that pressure and volume are inversely proportional—as one gets higger, the other gets smaller. Mathematically, 

When the density of gas in the tire is doubled, pressure is doubled. 

When the volume of gas is decreased, the density, and therefore pressure, are increased. 

Here P, and V, represent the original pressure and volume, respectively, and P2 and V2 represent the second pressure and volume. This relationship is known as Boyle s Law after the 17th-century scientist Robert Boyle (see Chapter 3) who first described it. Boyles Law, however, only holds true assuming that the temperature and number of gas particles remain the same. 

A scuba diver swimming underwater breathes compressed air at a pressure of 2 atmospheres. If she holds heT breath while returning to the surface, by how much does the volume other lungs tend to increase  

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