MGCCC, Perk Learning Lab
Created by Tara L. Moore
GAS LAWS
Boyle’s Law: P1V1=P2V2, Temperature is constant
P1 = P2V2 V1 = P2V2 P2 = P1V1 V2 = P1V1
V1 P1 V2 P2
Charles’s Law: V1 = V2, Pressure is constant, Temperature must be in Kelvin T1 T2
V1 = V2T1 T1 = V1T2 V2 = V1T2 T2 = V2T1
T2 V2 T1 V1
Gay-Lussac’s Law: P1 = P2, Volume is constant, Temperature must be in Kelvin T1 T2
P1= P2T1 T1 = P1T2 P2 = P1T2 T2 = P2T1
T2 P2 T1 P1
Combined Gas Law: P1V1 = P2V2, Temperature must be in Kelvin
T1 T2
P1=P2V2T1 V1=P2V2T1 T1=P1V1T2 P2=P1V1T2 V2=P1V1T2 T2=P2V2T1
T2V1 T2P1 P2V2 T1V2 T1P2 P1V1
Dalton’s Law of Partial Pressures
PT = P1 + P2 + P3 + …….
Patm = Pgas + PH2O
One of the very most important things to remember when plugging values into these equations is that the units must coincide. For example, if you are given one pressure value in atm and one pressure value in mm Hg, before you can plug these values into an equation, you must convert one of them so the unit values match. The matching units will allow you to cancel. This applies to pressure, volume and temperature.
CONVERSION FORMULAS
°F= 1.8°C + 32° °C= (°F - 32°) (remember 5/9 =1.8)
K = °C + 273° 1.8
1 atm = 760 torr= 760 mm Hg = 101,325 Pascals=101.325 kilo-Pascals
Ideal Gas Law: PV= nRT STP= Standard Temperature and Pressure
P= pressure in atm Standard Temperature = 273 K
V= volume in L Standard Pressure = 1 atm
n= number of moles 1 mole of any gas at STP occupies 22.4L
T= temperature in K
R= constant = 0.0821 (L*atm)/(mole*K)
P=nRT V=nRT n=PV R=PV T=PV
V P RT nT nR
n= m where m= mass in grams, MW= molecular weight g/mol: PV = mRT
MW MW
m=PVMW MW=mRT D=MWP
RT PV RT
Or
MW=DRT
P
Density = g/L