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1、Review1The standard Gibbs energy of reaction in solution the standard Gibbs energy formation(标准生成吉布斯自由能)the standard reaction Gibbs energy(反应的标准吉布斯自由能变)1The solvent and solute need distinguishand the solution is dilute(稀溶液).The standard state of each reactant and product is ci=1mol.dm-3 and the solu
2、tion submit Henrys law hypothetical.=+c denote the saturated solubility of each solute 22 The response of equilibria to the conditions1How equilibria respond to pressure The standard equilibrium constant is independent of the pressure,but the equilibrium composition depends on the pressure.3Le Chate
3、liers principle:A system at equilibrium,when subjected to a disturbance,responds in a way that tends to minimize the effect of the disturbance.42 effect of inert gas(惰性气体)on equilibrium1.If an inert gas is added to an equilibrium mixture of gases at constant temperature and volume,there is no effect
4、 on the equilibrium.2.If adding an inert gas at constant temperature and pressure which has the same effect as lowering the original gas partial pressure.53 The response of equilibria to temperatureThe van t Hoff equation is an expression for the effect of temperature on the standard equilibrium con
5、stant Ko.Here is the standard reaction enthapy at the temperature T.6(1)If varies only slightly with temperature(2)If depends on temperature,7Specially,when the heat capacities(热容)of reactants and products is the mean value,the value of is constant,then 8化学平衡移动规律当升高系统温度时,平衡向能降低温度(吸热)的方向移动,降低系统温度,平衡向能升高温度(放热)的方向移动;当增加系统压力时,平衡就向能减小压力(即减少气体物质的物质的量)的方向移动;当降低系统压力时,平衡就向能增大压力(即增加气体物质的物质的量)的方向移动。当增加反应物浓度时,平衡就向能减少反应物浓度的方向移动。当减少生成物浓度时,平衡就向能增加生成物浓度的方向移动。9