Equilibria

Question 1

Reversible reactions

Answer 1

Reactants & products will be found in reaction vessel at ‘end’ of reaction

Question 2

What will be established after a while in a closed system?

Answer 2

Equilibrium

Question 3

Dynamic equilibrium

Answer 3

1) Concentration of reactant & product are constant
2) Rate of forwards & backwards reaction are equal

Question 4

Le Chatelier’s Principle

Answer 4

Any change imposed upon a system will be opposed by the system to maintain equilibrium

Question 5

How do catalysts change equilibrium?

Answer 5

Don’t change equilibrium - rate of forwards & backwards reaction are both increased equally

Question 6

Increased temperature

Answer 6

Equilibrium moves in endothermic direction to oppose this increase in temperature

Question 7

Decreased temperature

Answer 7

Equilibrium moves in exothermic direction to oppose this decrease in temperature

Question 8

Increased pressure

Answer 8

Equilibrium shifts to lower pressure by favoring side with fewer molecules that opposes increase in pressure

Question 9

Decreased pressure

Answer 9

Equilibrium shifts to higher pressure by favoring side with more molecules to oppose this decrease in pressure

Question 10

Increased concentration of a substance

Answer 10

Equilibrium moves to decrease concentration

Question 11

Decreased concentration of a substance

Answer 11

Reaction moves to increase the concentration

Question 12

K

Answer 12

Relative proportion of reactant & product in equilibrium reaction

Question 13

Kc

Answer 13

Kc= [product]/[reactant]

Question 14

Unit for concentration

Answer 14

moldm-3