You fill a balloon with helium gas to a volume of 2.68L at 23°C and 789mmHg. Then you release the balloon and it rises. What will the volume be when the pressure drops to 632mm Hg if the temperature remains the same?

Answer : The final volume of balloon will be, 3.35 L

Explanation :

Boyle's Law : It is defined as the pressure of the gas is inversely proportional to the volume of the gas at constant temperature and number of moles.

or,

where,

= initial pressure = 789 mmHg

= final pressure = 632 mmHg

= initial volume = 2.68 L

= final volume = ?

Now put all the given values in the above equation, we get:

Therefore, the final volume of balloon will be, 3.35 L