1. City and Islington College
Equilibrium Problems
David Martin
City and Islington College
To Print
Students Name: …………………………………………………………………..

2. Topic Aims Method Equipment Duration Chemistry – Equilibria
This worksheet provides some exercises to help teach the topic of equilibria
Level
Level 3
Method
PowerPoint slides (hand-out) – ALL SLIDES to print out (apart from Slide 2) Answers are from slide 5 to 6
Work through the slides at the learners work through the hand-outs
Equipment
Laptop & Projector
Hand-out
Pens
Duration
>5-10 Minutes
Hidden

3. Equilibrium Problems Equilibrium Reaction Problems
Predict which direction the equilibrium reactions will move – answer left or right
1) Changing the pressure
a) H2C=CH2 (g) + H2O (g) CH3CH2OH (g) - the pressure is doubled
____________________________________________________________________
b) 2CO (g) + O2 (g) CO2 (g) - the pressure is increased
c) H2 (g) + I2 (g) 2HI (g) - the pressure is reduced
d) N2O4 (g) NO2 (g) - the pressure is halved
e) 3Fe (s) + 4H2O (g) Fe3O4 (s) + 4H2 (g) - the pressure is doubled
To Print

4. Equilibrium Problems 2) Changing the temperature
a) N2 (g) + 3H2 (g) NH3 (g) ∆H = -92 KJmol-1
Raise the temperature from 650K to 720K.
____________________________________________________________________
b) Ag2CO3 (s) Ag2O (s) + CO2 (g) ∆H = KJmol-1
Reduce the temperature from 450K to 400K.
c) CaCO3 (s) CaO (s) + CO2 (g) ∆H = KJmol-1
The temperature is reduced from 1200K to 1000K.
d) H2 (g) + I2 (g) HI (g) ∆H = +2.9 KJmol-1
The temperature is increased from 500K to 700K.
e) N2 (g) + O2 (g) 2NO (g) ∆H = KJmol-1
The temperature is decreased from 1500K to 1100K.
To Print

5. ANSWERS
To Print

6. Equilibrium Problems Equilibrium Reaction Problems
Predict which direction the equilibrium reactions will move – answer left or right
1) Changing the pressure
a) H2C=CH2 (g) + H2O (g) CH3CH2OH (g) - the pressure is doubled
A = Right the side with the least moles of gas
b) 2CO (g) + O2 (g) CO2 (g) - the pressure is increased
B = Right The side with the least moles of gas
c) H2 (g) + I2 (g) 2HI (g) - the pressure is reduced
C = no change moles of gas the same on both sides
d) N2O4 (g) NO2 (g) - the pressure is halved
D = Right the side with the most moles of gas
e) 3Fe (s) + 4H2O (g) Fe3O4 (s) + 4H2 (g) - the pressure is doubled
E = no change moles of gas the same on both sides
To Print

7. Equilibrium Problems 2) Changing the temperature
a) N2 (g) + 3H2 (g) NH3 (g) ∆H = -92 KJmol-1
Raise the temperature from 650K to 720K.
A = Left the endothermic direction
b) Ag2CO3 (s) Ag2O (s) + CO2 (g) ∆H = KJmol-1
Reduce the temperature from 450K to 400K.
B = Left the exothermic direction
c) CaCO3 (s) CaO (s) + CO2 (g) ∆H = KJmol-1
The temperature is reduced from 1200K to 1000K.
C = Left the exothermic direction
d) H2 (g) + I2 (g) HI (g) ∆H = +2.9 KJmol-1
The temperature is increased from 500K to 700K.
D = Right the endothermic direction
e) N2 (g) + O2 (g) 2NO (g) ∆H = KJmol-1
The temperature is decreased from 1500K to 1100K.
E = Right the exothermic direction
To Print

8. For further information please contact The STEM Alliance or visit