AP Chemistry A. Allan Chapter 5 - Gases 5.1 Pressure A. Properties of gases 1. Gases uniformly fill any container 2. Gases are easily compressed 3. Gases mix completely with any other gas 4. Gases exert pressure on their surroundings a. Pressure = force/area B. Measuring barometric pressure 1. The barometer a. Inventor - Evangelista Torricelli (1643) 2. Units a. mm Hg (torr) (1) 760 torr = Standard pressure b. newtons/meter2 = pascal (Pa) (1) 101,325 Pa = Standard pressure c. atmospheres (1) 1 atmosphere = Standard pressure 5.2 The Gas Laws of Boyle, Charles, and Avogadro A. Boyle's Law (Robert Boyle, 1627 - 1691) 1. the product of pressure times volume is a constant, provided the temperature remains the same kPV = a. P is inversely related to V