Chapter 5 Gases Flashcards
V/T=V/T
Charles’s Law
PV=PV
Boyle’s Law
V/n=V/n
AVagadro’s Law
P/T=P/T
Gay-Lussac’s Law
Ideal Gas Law
PV=nRT
mRT=MVP
DRT=MP
Value of R
.08206 atm
8.314 kPa
Dalton’s Law of Partial Pressures
Ptotal=Pa+Pb+Pc=xaPa+xbPb+xcPc
More useful: xa=na/ntotal=Pa/Ptotal
Collecting Gas over Water
Patm=Pgas+Pwv
Hydrostatic Pressure
Pressure due to water
Diffusion
Random mixing of gases
Effusion
Gas particles leave a small hole in container
Kinetic Energy Formula
KE=1/2mv^2
Same gas, different T
T1/KE1=T2/KE2
T1/v1^2=T2/v2^2
T1/(rate1)^2=T2/(rate2)^2
Different gas, same T==> Graham’s law of effusion
Ta=Tb
KEa=KEb
Ma(ratea)^2=Mb(rateb)^2
Ma(va)^2=Mb(vb)^2
Real Gas ==> Correct V & P
Compare real volume to ideal, and real pressure to ideal
Real V > Ideal V
Real P < Ideal P
— This is due to the fact that in ideal gasses it is assumed that the particles have no volume (V) and that they have no intermolecular attraction (P)
When do real gases get closer to being ideal?
High T
Low P
Small Particles
Nonpolar - less IM attraction
Pressure formula
P=F/A
Pressure=Force/Area
To increase pressure: More force, less SA
Temperature is also called…
Average Kinetic Energy
Dalton’s Law of Partial Pressures
Ptotal=P1+P2+P3…
Pressure ratio = mole ratio
Mole Fraction is equal to…
Pressure Fraction
X1=n1/ntotal=P1/Ptotal
Kinetic Molecular Theory
Gases are made up of widely separates, infinitely small particles
Movements of gas particles are:
1) Very Fast
2) Random
3) In generally straight lines
4) Involved in many, elastic collisions
5) Not affected by IM attraction
6) Particles have no volume
Graham’s Law of Effusion (with t)
tA/tB=-/(MA/MB)
Combined Gas Law
PV/nT=PV/nT
