Equilibrium

Question 1

equilibrium

Answer 1

reached when the concentrations of reactants and products become constant

Question 2

dynamic equilibrium

Answer 2

forward and backward reactions are still occurring

Question 3

forward reaction

Answer 3

reaction from left to right (reactants to products)

Question 4

backward reaction

Answer 4

reaction from right to left (products to reactants)

Question 5

equilibrium in terms of forwards and backwards reactions

Answer 5

rate of forward reaction equal to rate of backward reaction

Question 6

equilibrium is dynamic

Answer 6

reaction has not stopped but both forward and backward reactions are occurring at the same rate

Question 7

equilibrium is achieved in a closed system

Answer 7

both reactants and products and react with each other no exchange of matter with surroundings

Question 8

concentrations of reactants and products remain constant at equilibrium

Answer 8

they are being produced and destroyed at an equal rate

Question 9

at equilibrium there is no change in macroscopic properties

Answer 9

color/density do not change because dependent on concentrations of mixture

Question 10

equilibrium can be reached from either direction

Answer 10

same equilibrium mixture will result under same conditions can have all reacts, all products or mixture of both

Question 11

equilibrium position

Answer 11

proportion of reactant and product in equilibrium mixture

Question 12

equilibrium position lies to the right

Answer 12

mixture contains predominantly products

Question 13

equilibrium position lies to the left

Answer 13

mixture contains predominantly reactants

Question 14

equilibrium constant equation (Kc)

Answer 14

Question 15

What does the magnitude of Kc tell you?

Answer 15

Kc > 1 reaction has very high conversion of reactants to products

Kc < 1 reaction hardly proceeds

Question 16

reaction quotient

Answer 16

• find Kc at equilibrium
• measures the relative amount of products and reactants present during a reaction at a particular point in time

Question 17

What does the magnitude of the quotient compared to the equilibrium constant tell us?

Answer 17

Q = Kc reaction is at equilibrium

Q < Kc reaction proceeds to the right (favors products)

Q > Kc reaction proceeds to the left (favors reactants)

Question 18

What is Kc for an inverse reaction

Answer 18

1/Kc

Question 19

Kc for a multiple of a reaction

Answer 19

Kc^x

Question 20

Kc when add two reactions

Answer 20

Kc1 + Kc2

Question 21

Le Chatelier’s principle

Answer 21

when a system at equilibrium is subjected to a change, it will respond in such a way as to minimize the effect of the change

Question 22

Effect of changing concentration on equilibrium (increase conc of reactants)

Answer 22

• forward reaction rate increases
• new concentrations of reactants/products
• equilibrium shifts in favor of products

Question 23

effect of changing pressure on equilibrium position (increase pressure of reaction)

Answer 23

• seeks to decrease pressure
• shift in equilibrium position to favour side with smaller number of molecules
• Kc will remain the same

Question 24

effect of changes in temperature on equilibrium position (decrease temperature)

Answer 24

• produces heat
• favours exothermic reaction
• Kc will change depending on shift
• to right will increase Kc

Question 25

effect of catalyst on equilibrium position

Answer 25

• no change in position
• just enables equilibrium to be achieved more quickly
• Kc does not change value