Chapter 19 - Equilibrium Flashcards
What is a homogenous equilibrium?
All species are in the same physical state
What is a heterogeneous equilibrium?
Contains species in at least two different physical states
How do we calculate equilibrium concentrations?
Use the equation to work out equilibrium amounts of all species
Convert these into concentrations, using the total volume of the container
Substitute the concentrations into the Kc expression
How do we determine a value of Kc experimentally for an esterification reaction?
In conical flask, mix together 0.1 mol CH3COOH and 0.1 mol CH3CH2CHOH. Add a measured volume of aqueous Hcl as an acid or catalyst to the flask
Add the same measured volume of aq hcl to a second conical flask as a control
Stopper both flasks and leave for a week to reach equilibrium
Carry out a titration on the equilibrium mixture using a standard solution of sodium hydroxide
Repeat the titration with the control to determine the amount of acid catalyst that has been added
How do we work out mole fraction?
Divide number of moles by total number of moles
What is important to remember when calculating mole fractions?
No. of moles is proportional to the volume of a gas
