Chemical Kinetics Flashcards
indicates whether or not a reaction is spontaneous
Gibbs Free Energy (∆G)
± ∆G = endergonic = energy absorbed = nonspontaneous
+ ∆G
± ∆G = exergonic = energy given off = spontaneous
- ∆G
difference between the free energy of the products and the reactants
free energy change of the reaction (∆G(rxn))
energy is absorbed, indicated by positive free energy, non spontaneous
endergonic
energy is given off, indicated by negative free energy, spontaneous
exergonic
endergonic and exergonic are related to _____; they are not interchangeable with endothermic and exothermic because they are related to enthalpy
free energy
states that a reaction rate is proportional to the number of effective collisions between reacting molecules
collision theory
only happens when molecules are in proper orientation and have enough kinetic energy to exceed the activation energy
effective collision
a mathematical way of representing collision theory
Arrhenius equation
Arrhenius equation
k = Ae^-(Ea/RT)
where:
k = rate constant
A = pre-exponential factor
in the Arrhenius equation:
low activation energy (Ea) and high temperature (T) make the negative exponent _____ (bigger or smaller), which _____ (increases or decreases) the rate constant (k)
smaller; increases
radioactive decay for first-order reaction
[A]t = [A]o * e^(-kt)
where: [A]t = [A] at time t [A]o = initial [A] k = rate constant t = time
