5.1.2 How far?

Question 1

What is the equilibrium constant?

Answer 1

Kc

Question 2

How to work out Kc? (experiment) Part 1

Answer 2

Preparing equilibrium mixture
1. use burettes to prepare a mixture of COOH , alcohol and dilute sulphuric acid
2. Swirl and bung tube. Leave mixture to reach equilibrium

Question 3

How to work out Kc? (experiment) Part 2

Answer 3

Titrating equilibrium mixture
1. Rinse 250cm3 volumetric flask with distilled water
2. Use a funnel to transfer mixture into the flask. Rinse boiling tube with distilled water and add washings to volumetric flask
3. Use distilled water to make up solution to 250cm3. Add stopper and invert and shake
4. Use pipette to transfer 25cm3 to conical flask
5. Add few drops of phenolphthalein to conical flask
6. Add NaOH to burette
7. Add NaOH to the mixture until end point (pink)
8. repeat until concordant results

Question 4

What is the relationship between Kc and products/ reactants?

Answer 4

• The larger the kc then the equilibrium favours the products
• The smaller the kc then the equilibrium favours the reactants

Question 5

Effect of temperature of Kc of an exothermic reaction

Answer 5

Effect of temperature of Kc of an exothermic reaction

Question 6

Effect of temperature of Kc of endothermic reaction