Gas Laws Chemistry Mrs Coyle Factors Affecting Gas

Gas Laws Chemistry Mrs. Coyle

Factors Affecting Gas Pressure • Number of Moles (Amount of gas) – As the number of particles increases, the number of collisions with the container wall increases. • Volume – The smaller the volume, the greater the pressure exerted on the container. • Temperature – As temperature increases, kinetic energy increases, increasing the frequency of collision. Thus pressure increase.

If Mass and Temp are Constant

If Mass and Pressure are Constant

Boyle’s Law P 1 V 1=P 2 V 2 T constant # moles constant P vs V hyperbola Isotherm P High Temp V

Charles Law V 1 T 1 = V 2 T 2 P constant # Moles constant Isobar V T (K)

Guy-Lussac P 1 T 1 = P 2 T 2 V constant # moles Constant isochoric P T

Combined Gas Law P 1 V 1 = T 1 P 2 V 2_ T 2

Ideal Gas Law: P V = n R T P = pressure Pa = N/m 2 V = volume measured in m 3 n =# of moles T = temperature K R=Universal gas constant =8. 314 k. Pa L / (mol K) =0. 0821 L atm/(mol K) =62. 3 mm. Hg L/(mol K)

Dalton’s Law of Partial Pressures • Ptot=P 1+P 2+…. • Total pressure of a mixture of gases in a container is the sum of the individual pressures (partial pressures) of each gas, as if each took up the total space alone. • http: //www. wwnorton. com/college/chemistr y/gilbert/tutorials/interface. asp? chapter=ch apter_08&folder=daltons_law

Ideal Gas Laws mostly hold at: • Low pressure • High temperature