Chemical equilibrium - ES

Question 1

Equilibrium definition

Answer 1

when the rate of the reverse reaction is equal to the rate of the forward reaction, it is then at dynamic equilibrium

Question 2

Features of equilibrium

Answer 2

forwards and reverse reactions are both happening, but at the same rate, so the concentration of each substance is staying constant. Can only happen in a closed system

Question 3

What happens to the equilibrium when there aren’t equal concentration of reactions and products

Answer 3

the equilibrium position can be to the right (more products) or to the left (more reactants)

Question 4

Graph of when more reactants are produced at equilibrium

Answer 4

https://www.siyavula.com/read/za/physical-sciences/grade-12/chemical-equilibrium/images/764b1c1dce0bfcba7f7ced47ae70771c.png
RHS

Question 5

Graph of when more products are produced at equilibrium

Answer 5

https://www.siyavula.com/read/za/physical-sciences/grade-12/chemical-equilibrium/images/764b1c1dce0bfcba7f7ced47ae70771c.png
LHS

Question 6

Le Chateliers principle

Answer 6

if a reaction is at equilibrium and then a change is made in any of the conditions (Temp, Pressure, Conc) then the position of equilibrium will shift in the direction that minimises the change

Question 7

Changing the pressure at equilibrium

Answer 7

increasing pressure shifts the equilibrium in the direction with fewest gas molecules
decreasing pressure would shift the equilibrium to the side with the most gas molecules

Question 8

Changing the temperature at equilibrium

Answer 8

increasing the temperature shifts the equilibrium position in the endothermic direction (this takes in heat, reducing the temperature, so minimising change)
decreasing the temperature would shift the equilibrium position in the exothermic direction

Question 9

Changing the concentration at equilibrium

Answer 9

If one of the reactants conc increases the equilibrium position would shift to the right, minimising the change
If one of the reactants conc decreases the equilibrium position would shift to the left, minimising the change
If one of the products conc increases the equilibrium position would shift to the left, minimising the change
If one of the products conc decreases the equilibrium position would shift to the right, minimising the change

Question 10

Adding a catalyst at equilibrium

Answer 10

a catalyst does not change the position of equilibrium as a catalyst speeds up the rate of both the forward and reverse reaction equally. But it will reach equilibrium quicker