## physical chemistry

 Pressure
 pressure equals force divided by the area p=F/A
 Temperature
 in science it is always measured in Kelvin (Celsius + 273.15 = Kelvin)
 Equation of state for perfect gases
 pV=nRT, at constant temperature boyles law p=1/V
 Thermal equilibrium
 When two bodies in contact have the same temperature and there is no net flow of energery between them
 Isotherms
 Each constant temperature curve on a graph of pressure versus inverse of volume (p = 1/V)
 Isobars
 represent change in atmospheric pressure on a weather map, in increments of 4 mbar or 400pa
 Compression factor
 Z=Vm/Vm(perfect) // Vm = V/n = RT/p (this is molar volume equation volume divided by number of moles in that volume or R x temp divided by pressure) Z=pVm/RT
 Van der Waals equation of state
 p=(nRT/(V-nb))-a(n/V)^2 p=(RT/Vm-b)-a/Vm^2
 potential energy vs particle separation
 potential energy = mass x gravity x height gravity=9.81 m s^-2 Coulomb potential energy = Q1Q2/4 x pi x r
 attractive and repulsive forces
 critical temperature Tc
 The temperature at which a gaseous state transforms continuously into the condensed state and at no stage is there a visible surface between the two states of matter (a gas cannont be condensed to a liquid by the application of pressure unless the temperature is below the critical temperature) vapour is the gaseous phase of a substance below its critical temperature
 critical constants Tc,pc,Vc
 All three of these temperature pressure and volume make up the critical constants
 closed systems
 can exchange energy but not matter with its surroundings
 work w
 a system does work when it causes motion against an opposing force w=mgh (mass x gravity x height) expansion work = p(external) x hA = p(external) x dV Work=-nRTln(Vfinal/Vinitial) Work=pdV (pressure x delta volume)
 heat q
 the process of transferring energy as a result of a temperature difference between the system and its surrounding q heat capacity c=q/dT or q=c x dT
 internal energy U=q+w
 internal energy (U) = heat + work heat (q)=
 diathermic boundaries
 Walls/boundaries that permit heating as a mode of transfer of energy
 exothermic processes
 a process in a system that releases energy as heat
 first law of thermodynamics
 The internal energy of an isolated system is constant
 expansion work against constant pressure
 expansion work for isothermal reversible process
 Hydrostatic pressure
 hydrostatic pressure = denstiy x height x gravity density = mass/volume
 Equation of state for real gases
 good to know
 1 J = 1 Pa m^3
 Walls/boundaries that do not permit heating even though there is a difference in temperature on both sides
 endothermic process
 a process in a system that absorbs energy as heat
 open system
 can exchange both energy and matter with its surroundings
 isolated system
 can exchange neither matter nor energy with its surroundings
 Force
 pressure x area
 partial pressure
 xj = nj/n partial pressure = amount of j molecules in the mixture divided by the total amount
 Maxwell distribution
Tagged In :

## Get help with your homework

Haven't found the Essay You Want? Get your custom essay sample For Only \$13.90/page

Sarah from studyhippoHi there, would you like to get such a paper? How about receiving a customized one?

Check it out