Ap Chemistry: Le Chatelier's principle + unknown concentrations

Question 1

What does leChatelier’s principle state

Answer 1

when stress is applied to a reaction at equilibrium, the reaction will shift in a direction to release the stress

Question 2

What is the “stress”

Answer 2

anything that will cause us to not have products and reactants be in a ratio related to Kc

Question 3

What are the types of stresses

Answer 3

volume, pressure, temperature(heat), molarity

Question 4

On a graph how do you know when equilibrium is reached

Answer 4

when the line is a straight line

Question 5

what happens to Qc when you add more reactants; where will it shift

Answer 5

Qc

Question 6

what happens to Qc when you add more products; where will it shift

Answer 6

Qc>k; shift to the reactants to level it out

Question 7

what happens when we remove products from the mixture

Answer 7

Qc

Question 8

what happens when we remove the reactants from the mixture?; where will it shift

Answer 8

Qc>K; and the reaction will shift toward the reactants to replace what was lost

Question 9

how can you dilute concentrations in a reaction

Answer 9

add water

Question 10

what would happen to the molarities of the aqueous solutions

Answer 10

they would decrease

Question 11

what will cause a no change in the equilibrium

Answer 11

when the moles of the aqueous = moles of the water

Question 12

what happens when the equation has two sides of unequal moles, where will the water shift?

Answer 12

the reaction would shift to the side with more moles

Question 13

What happens to the volume when you increase pressure, and where will it shift?

Answer 13

decrease the volume; shift to the side with fewer moles

Question 14

what happens to the volume when you decrease the pressure? where will it shift

Answer 14

increase the volume; shift to the side with more moles

Question 15

what happens when moles of gas are equal on both sides?

Answer 15

there is no shift

Question 16

what does it mean when a reaction is endothermic

Answer 16

heat is a reactant or heat + reaction = products

Question 17

what does it mean when a reaction is exothermic

Answer 17

heat is a product or reaction = products + heat

Question 18

what is the goal of Le Chatelier in regards to temperature changes?

Answer 18

Get the reaction to a New Kc

Question 19

if the temperature increased in an endothermic reaction, what will happen to k, and where will it shift toward

Answer 19

K will increase and it will shift to the products

Question 20

if the temperature increased in an exothermic reaction, what will happen to k, and where will the reaction shift

Answer 20

K will decrease and it will shift towards the reactants

Question 21

if the temperature decreased in an endothermic reaction, what will happen to K, and where will the reaction shift?

Answer 21

K will decrease; shift towards reactants

Question 22

if the temperature decreased in an exothermic reaction, what will happen to K, and where will the reaction shift

Answer 22

K will increase; shift towards the products

Question 23

does a catalyst affect the equilibrium?

Answer 23

No

Question 24

if an initial concentration is not given, what do you use?

Answer 24

x