Rowan Naga Chemistry Revision 1 | P a g eChapter Two: Liquid State Clapeyron Equation: = Rate by which V.P. changes with temp. V= Vi - Vf L= Latent heat of evaporation for transformation of (1) mole of liquid to vapor. (Enthalpy) Derivation of equation: (copied) Use this equation when solving:
Rowan Naga Chemistry Revision 2 | P a g eProperties of Liquid: 1)Evaporation: ( Endothermic) ( from liquid to vapor)Conditions needed: 1. KE in excess than the average volume. 2. Must occupy a position of the liquid surface. Factors that increase evaporation rate: 1.Increased temperature. 2.Increased surface area of liquid. 3.Increased intermolecular attractions. Latent Heat of Evaporation: (Enthalpy) -Definition: The amount of energy in the form of heat required to evaporate (1) mole of liquid at constant temperature. -Water Hevap. = +44 kj/mole 2)Condensation: ( Exothermic) ( from vapor to liquid )Hevap. + Hcond. = 0Vapor Pressure: Pressure that the vapor exerts when the liquid and vapor coexists in conditions of dynamic equilibrium.