120 likes | 239 Views
Test Review. Thermodynamics. Factors effecting the rates of reaction. Number of collisions Concentration of reactants Temperature Surface area Catalysts. Potential Energy Diagrams. Activated Complex Heat of Reaction Exothermic vs Endothermic Result of a catalyst. Exothermic Reactions.
E N D
Test Review Thermodynamics
Factors effecting the rates of reaction • Number of collisions • Concentration of reactants • Temperature • Surface area • Catalysts
Potential Energy Diagrams • Activated Complex • Heat of Reaction • Exothermic vs Endothermic • Result of a catalyst
Exothermic Reactions • Releases heat • Sign of DH is negative • Temperature of the surroundings increases
Endothermic reactions • Absorbs energy • Sign of DH is positive • Temperature of the surroundings decreases
Entropy • Solid < Liquid < Gas • Dissolving a solute into a solvent INCREASES entropy.
Specific Heat Calculations • Q = mcDT • Specific heat (c) = 4.18 J/goC • Use when you have a temperature change
Calculating heat of fusion • Q = mass x heat of fusion • Used only for a phase change • NO temperature change
Calculating Heat of Reaction • Sum of products – sum of reactants • H = nHf(products) - mHf(reactants)
Calculating DG • Determines whether a reaction is spontaneous. • DG + is nonspontaneous. • DG negative is spontaneous. • DG = DH-TDS