Topic 19 - Dynamic Equilibrium Flashcards Preview

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Flashcards in Topic 19 - Dynamic Equilibrium Deck (13)
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1
Q

Describe the decomposition of ammonium chloride

A

NH4Cl (s) —> NH3 (g) + HCl (g)

2
Q

Describe the dehydration of copper sulphate crystals

A

(heat)

CuSO4•5H2O (s) —> CuSO4 (s) + 5H2O (l)

3
Q

What is dynamic equilibrium?

A

When the concentrations of reactants and products will reach a certain balance and stay there.

The reactions are still taking place in both directions, but the overall effect is nil because the forward and backward reactions cancel each other out - they are taking place at exactly the same rate.

4
Q

What is needed for dynamic equilibrium to be achieved?

A

A closed system, so none of the reactants or products can escape.

5
Q

What are the 3 factors which affect the position of the equilibrium?

A

Temperature, pressure (of gas!!) and reactants & products

6
Q

What is the guiding principal?

A

Position of equilibrium shifts to counteract change

7
Q

What happens when you add some more reactant/product?

A

The position would shift in whichever direction used up the added substance

8
Q

What happens when you take away some of the reactant/product?

A

The equilibrium will shift in whichever direction creates more of the substance removed

9
Q

What happens when you increased the gas pressure?

A

The equilibrium shifts to reduce the pressure-> it shifts in whichever direction converts more moles of substance into less moles of substance

10
Q

What happens if you decrease the gas pressure?

A

The equilibrium shifts to increase the pressure -> it shifts in whichever direction converts less moles of gas into more moles of gas

11
Q

What happens if you increase the temperature?

A

The equilibrium shifts to decrease the temperature.
You will be given ΔH, and ΔH always shows the forwards reaction.
So, it shifts in whichever direction causes an endothermic reaction

12
Q

What happens in you decrease the temperature?

A

The equilibrium shifts to increase the temperature.
You will be given ΔH, and ΔH always shows the forwards reaction.
So, it shifts in whichever direction causes an exothermic reaction

13
Q

What happens when you use a catalyst in a reversible reaction

A

Nothing, because it speeds up the forwards and backwards reaction by the same amount