Module 5

• What is the Arrhenius Equation?

  k = Ae$-Ea/RT$
• What does the rate constant (k) represent in the Arrhenius Equation?

  It relates reaction rate to temperature
• What is a Clock Reaction?

  A reaction measuring time for a visible change
• How is Colorimetry used in chemistry?

  To measure light absorbed by a solution
• What does a Concentration-time Graph plot on its axes?

  Concentration on y-axis and time on x-axis
• What does the gradient of a Concentration-time Graph represent?

  The rate of reaction
• What is Continuous Monitoring in a rate experiment?

  Taking continuous measurements as the reaction progresses
• What is a First Order Reactant?

  A reactant whose rate doubles when concentration doubles
• How is the gradient calculated?

  Change in y ÷ change in x
• What is Half-life (t$_{1/2}$)?


  The time for concentration to halve
• What is the Initial Rate of a reaction?

  The rate at time t=0
• What does Order refer to in a reaction?

  A number relating rate to reactant concentrations
• How is Overall Order determined?

  Sum of the orders with respect to each reactant
• What is the Rate Constant (k)?

  A constant relating rate to reactant concentrations
• How can k be determined for a first order reaction?

  Using k = ln 2/t$_{1/2}$
• What does a Rate-concentration Graph plot on its axes?

  Concentration on x-axis and rate on y-axis
• What is the Rate-determining Step?

  The slowest step of a reaction
• What does the Rate equation relate?

  Rate to concentrations of reactants and k
• What is the Rate of Reaction?

  A measure of how quickly reactants are used
• What is a Reaction Mechanism?

  A step-by-step sequence of individual reactions
• What is a Second Order Reactant?

  A reactant whose rate quadruples when concentration doubles
• What is a Zero Order Reactant?

  A reactant that has no impact on the rate
• What is a Catalyst?

  A substance that speeds up a reaction
• How is Concentration defined?

  Amount of substance per unit volume of solution
• What characterizes an Endothermic reaction?

  It takes in energy from surroundings
• What is Equilibrium in a chemical reaction?

  Forward and reverse reactions occur at the same rate
• What is the Equilibrium Constant (K)?

  A value relating products and reactants at equilibrium
• How does temperature affect the Equilibrium Constant (K)?

  K is affected by temperature changes
• What is Heterogeneous Equilibrium?

  Equilibrium involving substances in different states
• What is Homogeneous Equilibrium?

  Equilibrium involving substances in the same state
• What is K$_{c}$?


  Equilibrium constant based on concentrations
• How is K$_{c}$ calculated?


  Products' concentrations raised to stoichiometric coefficients
• What is K$_{p}$?


  Equilibrium constant based on partial pressures
• How is K$_{p}$ calculated?


  Products' partial pressures raised to stoichiometric coefficients
• What does Partial Pressure (P$_{A}$) represent?


  Pressure exerted by one gas in a mixture
• What is the Acid Dissociation Constant (K$_{a}$)?


  Extent of acid dissociation
• How is pK$_{a}$ calculated?


  pK$_{a}$ = -log(K$_{a}$)
• What is a Bronsted-Lowry Acid?

  A proton donor
• What is a Bronsted-Lowry Base?

  A proton acceptor
• What is a Buffer Solution?

  A system that minimizes pH change