According to Charles's Law, if the pressure of a gas stays constant, when the temperature increases, the volume __________.

• skyluke89: The correct answer is "the volume increases".
  
  In fact, Charle's law states that when the pressure of a gas stays constant, the ratio between the temperature and the volume of the gas is constant:
  [tex] \frac{T}{V} =k[/tex]
  where T is the gas temperature and V is its volume. We see from the formula that, if the temperature T increases, since the ratio must remain constant, the volume of the gas V increases as well.
• Weser17:

  The volume increases is right for apex