Module 14: Kinetics

 Reaction rate
 The rate of change of a product in a chemical reaction.(459)
 controlled experiment
 Experiment in which one test is done under standard conditions, and all other tests are compared to those standard conditions.(462)
 control
 The test done under standard conditions in a controlled experiment.(462)
 In order to react, chemicals must collide with one another so that their electrons can either be ____________ or ______________.
 transferred or rearranged.(463)
 Why does higher temperature increase the chemical reaction rate?
 Because the reactant molecules (or atoms) move faster, increasing the chance for a collision.(463)
 Why does decreasing the concentration also decrease the chemical reaction rate?
 Because there are fewer reactant molecules (or atoms) to collide with one another.(463)
 When a solid object gets crushed, the molecules get spread out over a larger area. Chemists call this an increase in the ______________ of a reactant.
 surface area(463)
 Increasing the surface area of a reactant increases reaction rate because:
 the molecules (or atoms) of the reactant can more easily mingle with the molecules (or atoms) of the other reactants.(463)
 Rate equation:
 R = k[A]x[B]y
 Exponents in the rate equation are called the ________ of the chemical reaction with respect to the ____________ they affect.
 order, reactant (465)
 Adding the exponents in the rate equation gives you:
 the overall order of the chemical equation (465)
 When the rate of a chemical reaction is unaffected by the concentration of one of its reactants, the exponent of the rate equation is ______ for that reactant.
 zero (471)
 The reaction rate orders for a chemical reaction must be determined __________-ly. They are [equal/not equal] to the stoichiometric coefficients in the chemical equation.
 experimentally, not equal (474)
 Instantaneous rate
 The rate of change at a particular moment, calculated from rate equation. (475)
 Chemical reactions never actually __________; there will always be some __________ left.
 finish, reactants (476)
 Since the rate constant [increases/decreases] dramatically with increasing temperature, the reaction rate does as well.
 increases (477)
 The rate of many chemical reactions doubles for every ______ increase in temperature.
 10° Celsius (478)
 catalyst
 A substance that alters the rate of a chemical reaction without changing concentration throughout the course of the reaction. (479)
 Catalysts speed up the reaction rate without actually ____________________ in the chemical reaction.
 getting used up (480)
 Catalysts speed up reaction rates by doing what?
 Lowering the activation energy of the reaction. (481)
 Heterogeneous catalysts
 Catalysts that are in a different phase than the reactants. (481)
 Homogeneous catalysts
 Catalysts that have the same phase as at least one of the reactants. (481)
 Reaction mechanism
 A series of chemical equations that tells you the step-by-step process by which a chemical reaction occurs. (483)