CHEM 1212 1nd Edition Exam 2 Study Guide Lectures 7 16 Chapter 15 If the concentration of a reactant is increased the reaction rate will often increase as well Chemical reactions occur more rapidly at higher temperatures Rate law equation k A m B n Homogeneous catalyst is included in rate equations In zero order reactions the reaction rate is independent of the reactant concentration 1st order integrated rate equation ln R t R 0 kt 2nd order integrated rate equation 1 R t 1 R 0 kt 0 order integrated rate equation R 0 R t kt Orders determined from graphs o Find one with straight line o If straight line is on graph of R t vs t then it is 0 order o If straight line is on ln R t vs t the it is 1st order o If straight line is on 1 R t vs t then it is 2nd order Half life o Longer half life slower reaction o Usually involving 1st order processes o Half life and 1st order k t1 2 693 K t1 2 is independent of concentration The Arrhenius Equation o K rate constant Ae Ea RT o Frequency factor A is temperature independent o Ln K2 K1 Ea R 1 T2 1 T1 Chapter 16 Equilibrium constant K o K C c D d A a B b Solids not included in equilibrium K equation Water is not included in equilibrium K equation Kp PcPd PaPb o Kp concentrations in partial pressure K 1 product favored K 1 reactant favored Reaction quotient Q used when reaction is not at equilibrium o Q C c D d A a B b If Q K then reactants must be converted to products to reach equilibrium If Q K then products much be converted to reactants to reach equilibrium When stoichiometric coefficients of a balanced equation are multiplied by some factor the Knew is the Kold raised to the power of the multiplication factor The equilibrium constants for a reaction and its reverse are the reciprocals of one another When two or more chemical equations are added to produce a net equation the equilibrium constant for the net equation is the product of the equilibrium constants for the added equations Chapter 17 In a neutral solution H3O OH 1 0x10 7 o Together 1 0x10 14 In acidic solution hydronium concentration is greater than OH concentration In basic solution hydronium concentration is less than the OH concentration pH scale o pH log H3O o pH 7 neutral o pOH log OH o pKw 14 00 pH pOH o pH 7 acidic o pH 7 basic Ionization constant o Ka H3O A HA o Ka 1 weak acid o Kb BH OH B o The weaker the acid the stronger the conjugate base o pKa logKa o As Ka increases acid strength increases o As pKa decreases acid strength increases o Ka x Kb Kw Kw 1 0x10 14 Acid base reactions o Mixing equal amounts moles of a strong base and strong acid produces a neutral solution