Chapter 1 Rates, equilibrium and pH Flashcards
What is the rate equation?
k[A]^m [B]^n
What is rate of reaction?
The change in concentration of a reactant or a product per unit time.
How do you calculate the overall order?
Sum of individual orders
What is meant by order?
The order of reaction with respect to a certain chemical shows how changing the concentration of that chemical affects the rate of reaction.
What is zero order?
- Shows rate of reaction doesn’t change with concentration
- Half life decreases with time
What is first order?
- As concentration halves, the rate of reaction halves
- Half life is constant
What is second order?
- As concentration halves, rate of reaction goes down by 4 (2^2)
- Half life increases
What are the units for rate?
mol dm^-3 s^-1
What is meant by half life?
Time take for the concentration of reactant to fall by half.
What is meant by the rate determining step?
Slower step in the reaction
What is the relation between the rate equation and rate determining step?
They have the same reactants
What is the Arhenius equation?
k=Ae^-Ea/RT
k - rate constant
T - temperature (K)
R - 8.13 JK-1 mol-1
Ea - activation energy
What is the Arhenius equation in the y=mx+c format?
lnk = -Ea/RT + lnA
What is a homogenous reaction?
All chemicals are in the same states
What is Kc?
Equilibrium constant for concentration
What is Kp?
Equilibrium constant for pressure
What is the mole fraction?
The proportion of a given substance that is present in the reaction mixture
What is partial pressure?
The pressure exerted by an individual gas if it occupied the whole vessel on its own
What is the algebraic equation for Kc?
Kc = [C]^c [D]^d / [A]^a [B]^b