W_ex = -P_ex * ΔV (1 J = Pa m 3) [when Pex is constant] q = m*C_sΔT q_sys = -q_surr C = q/ΔT => CΔT = q (heat capacity) ΔH = ΔU + PΔV ΔS = q_rev / T (q is usually in J, T is constant & in K) Δ_Ssurr = - ΔH/T (at constant pressure and temperature) ΔHr° = ΣnΔHf°(products) - ΣnΔHf°(reactants) ΔHr° = ΣnΔHf°(reactants) - ΣnΔHf°(products) *If using bond enthalpies* ΔSr° = ΣnSm° (product) - ΣnSm° (reactants) (elemental forms not equal 0) ΔS_vap = ΔH_vap/T_b (T_b is the boiling point) ΔGr = ΣnGm° (product) - ΣnGm° (reactants) ΔG = ΔH – TΔS (at constant temperature, ΔG in J or kJ)-------------------------T↑ => P_vap↑ cuz more molecules have energy to break IMF bonds. IMF↑ => P vap ↓ => T bp ↑ => ΔH vap ↑ => Viscosity↑ London forces ↑ with molecular weight! (If so big, can beat H-bonding) Endo => T↑ => K↑ => Products↑
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This note was uploaded on 05/22/2008 for the course CHEM 6B taught by Professor Crowell during the Winter '08 term at UCSD.