93 Views

Download Presentation
## Topic 1 Gases

- - - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - - -

**1.1 Ideal gases**The state equation of ideal gases The pressure-volume relationship — Boyle’s law V=constant×1/P or PV=constant The temperature-Volume relationship — Charles’ law V=constant×T or V/T=constant The quantity-volume relationship — Avogadro’s law V=constant×n V∝nT/P PV=nRT R--- Avogadro constant**Units of pressure**• 1 Pa=1 N.m-2 • 1 kPa=103 Pa • 1 MPa=106 Pa • 1 torr= 1 mmHg=133.322 Pa • 1 atm=760 torr=1.01325×105Pa • 1 bar=105 Pa=0.9869 atm =750.06 torr Micro view about pressure of gases**Value of R**• 8.3145 J.mol-1.K-1 • 0.083145 L.bar.K-1.mol-1 • 82.058 cm3.atm.mol-1.K-1 • 0.082058 L.atm.mol-1.K-1 • 1.98722 cal.mol-1. K-1 • 62.364 L.Torr.K-1. mol-1**1.2 Mixture of ideal gases**• Dalton law: Amagat law:**1.3 Real gasesdo not follow the ideal state equation**Internal pressure: induced by interaction between molecules Volume of gas molecules Kamerling-Onnes equation: van der Waals equation: b, molecular volume**Fugacity of real gases**The efficient pressure ,fugacity coefficient Determination of fugacity coefficient 1. Graphical method Measure P, Vm, T 2. Corresponding states method Compression factor, Z=pV/nRT**The parameters of critical states of real gases**Critical temperature Tc: Above which the gas can not be liquefied by increasing the pressure Cricital pressure Pc: The minimum pressure the gas could be liquefied at Tc Cricital volume Vc: The molar volume of the gas at Tc and Pc Vc, Tc and Pc the critical parameters Critical Point Data for Methane: Pc = 46.3 bar, Tc = 190.6 K, Vc =0.099 L mol-1, Zc = 0.29.**van der Waals equation:**The corresponding critical constants The corresponding states Corresponding temperature 对比温度 Corresponding pressure 对比压力 对比体积 Corresponding volume**Principle of corresponding states**At critical point all gases are equally nonideal.**PVm=ZRT**Newton diagram