1. 12.1 Characteristics of Gases

2. I. Properties of Gases A.Fluid – they are able to flow Diffusion

3. B. Low density – large distance between gas particles

4. C. Highly compressible – a small amount of pressure move gas particles closer together Low pressure Larger volume High pressure Smaller volume

5. D. Completely fill a container I 2 (s)  I 2 (g)

6. II. Measuring Gases Values of the FOUR gas variables - Amount of Gas (n): n = mass/molar mass Volume (V): 1 L = 1000 cm 3 Temperature (T): Measured in Kelvins Pressure (P): (see conversion sheet)

7. Scientists have specified a set of standard conditions called: standard temperature and pressure (STP) = 0 o C and 1.00 atm

8. Converting Temperature 15 o C = _____ K 312 K = _____ o C 15 o C + 273 312 K ‒ 273 288 25 o C = _____ o F (1.8)(25 o C) + 32 77 6.5 o F = _____ o C (6.5 o F ‒ 32) ÷ 1.8 ‒ 14.2 39

9. Converting Pressure Units The air pressure in a cabin of an airplane is 8.3 psi. What is this pressure in torr units? 430 torr 8.3 psi 1 atm 14.70 psi 1 atm 760 torr