Chapter 11 Summary Chem
Chapter 11
Gases
assumes both shape and vol of the container compressible, form homogenous w/ 1 another
D is smaller then liquids/solids and highly variable depending on T and P
Kinetic Molecular theory
3/2RT = total kinetic energy
½ mu2 = average kinetic energy Urms speed of mol with average kinetic energy, its inversely proportional to the square root of M
when T is the same
EX. Determine how much faster a helium atom moves, on average, than a carbon dioxide molecule at the same temperature.
The molar masses of He and CO2 are 4.003 and 44.02 g/mol, respectively.
Diffusion: mixing of gases at random motion & frequent collision
Effusion: escape of gas from a container to a region of vacuum
Gas Pressure
P= Force/area
Force: Newton or kg x m/s2
Pressure: Pascal or N/m2
Standard atm pressure
P= hdg
H: height, d: density; g: 9.80665 m/s2
1 atm* = 101,325 Pa = 760 mmHg* = 760 torr* = 1.01325 bar = 14.7 psi barometer: measure atmospheric pressure
Monometer: measure pressures other then atm pressure
Gas Laws
Boyles law: P at constatnt T is iversely prop to V
P1V1=P2V2
EX:Calculate the volume of a sample of gas at 5.75 atm if it occupies 5.14 L at 2.49 atm. (Assume constant temperature.)
Charles Law: V at constant P is directly prop to absolute T
V1/T1 = V2/T2
Avogadro law: V is directly prop to number of moles (n) at constant T and P
V1/n1 = V2/n2
EX: What volume in liters of water vapor will be produced when 34 L of H2 and 17 L of O2 react according to the equation: 2H2(g) + O2(g) → 2H2O(g)
34L of water will form
V is proportional to the n , the balanced equation determines in what volume ratio the reactants combine and the ratio of product volume to reactant volume. The amounts of reactants given are stoichiometeric amounts.
The Ideal Gas Equation OR PV= nRT d= PM/RT d: density(g/L) and M: molar mass(g/mol)
R: 0.08206 L amt/K mol
Standard Temperature and Pressure :
P= 1atm
T= 0C or 273.15K
V: 22.41L
Ex:
What pressure would be required
Gases
assumes both shape and vol of the container compressible, form homogenous w/ 1 another
D is smaller then liquids/solids and highly variable depending on T and P
Kinetic Molecular theory
3/2RT = total kinetic energy
½ mu2 = average kinetic energy Urms speed of mol with average kinetic energy, its inversely proportional to the square root of M
when T is the same
EX. Determine how much faster a helium atom moves, on average, than a carbon dioxide molecule at the same temperature.
The molar masses of He and CO2 are 4.003 and 44.02 g/mol, respectively.
Diffusion: mixing of gases at random motion & frequent collision
Effusion: escape of gas from a container to a region of vacuum
Gas Pressure
P= Force/area
Force: Newton or kg x m/s2
Pressure: Pascal or N/m2
Standard atm pressure
P= hdg
H: height, d: density; g: 9.80665 m/s2
1 atm* = 101,325 Pa = 760 mmHg* = 760 torr* = 1.01325 bar = 14.7 psi barometer: measure atmospheric pressure
Monometer: measure pressures other then atm pressure
Gas Laws
Boyles law: P at constatnt T is iversely prop to V
P1V1=P2V2
EX:Calculate the volume of a sample of gas at 5.75 atm if it occupies 5.14 L at 2.49 atm. (Assume constant temperature.)
Charles Law: V at constant P is directly prop to absolute T
V1/T1 = V2/T2
Avogadro law: V is directly prop to number of moles (n) at constant T and P
V1/n1 = V2/n2
EX: What volume in liters of water vapor will be produced when 34 L of H2 and 17 L of O2 react according to the equation: 2H2(g) + O2(g) → 2H2O(g)
34L of water will form
V is proportional to the n , the balanced equation determines in what volume ratio the reactants combine and the ratio of product volume to reactant volume. The amounts of reactants given are stoichiometeric amounts.
The Ideal Gas Equation OR PV= nRT d= PM/RT d: density(g/L) and M: molar mass(g/mol)
R: 0.08206 L amt/K mol
Standard Temperature and Pressure :
P= 1atm
T= 0C or 273.15K
V: 22.41L
Ex:
What pressure would be required