Reaction kinetics Flashcards
What is a limiting reactant
Reacting that is present in the correct stoichiometric amount
How do you calculate the % excess reactant?
%XS= (moles present-moles required)/moles required
How do you calculate % conversion and what letter is used to denote conversion?
% conversion=
moles of reactants used/ total moles of reactant in feed
X with a subscript of the reactant is used to denote
What are the two types of yield calculations?
- Percentage yield: actual yield/theoretical yield
- Atom economy: yield of desired products/yield of all products
Which 4 things can reaction rate be based on/expressed in terms of?
- Unit volume of reaction fluid
- Unit volume of reactor
- Unit S.A of solids in gas-solid system OR area of contact between 2-fluids
- Unit mass of solid in fluid-solid reactor e.g catalyst
What is the equation for rate of reaction equation?
r*i = dNi/dt * 1/ (thing based on)
N=number of moles of component, i
What are the factors affecting reaction rate?
-Heat transfer -> temp.
- Pressure/composition -> conc.
- Mass transfer -> conc.
- Catalyst -> conc.
What is the rate equation?
r=kCA^aCB^b
a,b- reaction order
k-rate constant
What are the units for the rate constant?
Dependent on reaction order
- Zero order: moldm^-3s^-1
- First order: s^-1
- Second order: moldm^-3s^-1
What is the the equation to show extentnof reversibility?
-dG = RTlnKp
If Kp is large, reactuon is basically irreversible, equilibrium position lies very far to product side
What is the Arrhenius equation?
k= Ae^(-Ea/RT)
How do you use Arrhenius equation graphically?
lnK=lnA-Ea/R*1/T
