Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

AS CHEMISTRY > EQUILIBRIA > Flashcards

EQUILIBRIA Flashcards

You may prefer our related Brainscape-certified flashcards:
Periodic Table flashcards Chemistry 101 flashcards AP® Chemistry flashcards Organic Chemistry 101 flashcards
1
Q

Define dynamic

A

Both forward and backward reactions are occurring simultaneously

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Outline the two features of dynamic equilibirum

A
  1. Forward and backward reactions are occurring at equal rates
  2. The concentrations of reactants and products stays constant
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Outline Le Chatelier’s PRinciple

A

If an external condition is changed the equilibrium will shift to oppose the change

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Describe the effects of increasing the temperature on equilibrium in an exothermic reaction

A

The equilibrium shifts to the products
To decrease the temperature
And oppose the shift
Giving a lower product yield

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Describe the effects of decreasing the temperature on equilibrium in an endothermic reaction

A

The equilibrium shifts to the products
To decrease the temperature
And oppose the shift
Giving a lower product yield

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Describe the effects of increasing the temperature on equilibrium in an endothermic reaction

A

The equilibrium shifts to the the reactants
To decrease the temperature
And oppose the shift
Giving a higher product yield

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Describe the effects of decreasing the temperature on equilibrium in an exothermic reaction

A

The equilibrium shifts to the the reactants
To decrease the temperature
And oppose the shift
Giving a higher product yield

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Why is a compromise temperature used

A

Lower temperatures give a higher yield
But slow the rate of reaction

Compromise temperatures give a reasonable rate and yield

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Describe the effects of decreasing the pressure on equilibrium

A

The equilibrium shifts to the side with more moles of gas
To increase the pressure
And oppose the shift
Giving a lower yield on the side with fewer moles

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Describe the effects of increasing the pressure on equilibrium

A

The equilibrium shifts to the side with more moles of gas
To increase the pressure
And oppose the shift
Giving a higher yield on the side with fewer moles

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Describe the effects of changing pressure on equilibrium when moles is equal either side

A

No effect on position of equilibrium

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Why is an increased pressure not often used to give a higher yield?

A

Expensive to produce (elctric for pumping to give high pressure)

Expensive equipment

Outweigh the higher yield and faster rate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Describe the effects of increasing the concentration of the reactants on equilibrium

A

The equilibrium shifts to the the reactants
To decrease the concentration
And oppose the shift
Giving a higher product yield

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Describe the effects of increasing the concentration of the products on equilibrium

A

The equilibrium shifts to the the products
To decrease the concentration
And oppose the shift
Giving a lower product yield

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Describe the effects of decreasing the concentration of the products on equilibrium

A

The equilibrium shifts to the the reactants
To increase the concentration
And oppose the shift
Giving a higher product yield

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Describe the effects of decreasing the concentration of the reactants on equilibrium

A

The equilibrium shifts to the the products
To increase the concentration
And oppose the shift
Giving a lower product yield

17
Q

Outline the effects of a catalyst on equilibirium

A

No effect on position of equilibrium

Speeds up the rate at which equilibrium is achieved

Speeds up the rate of the forward and backward reaction equally

18
Q

Outline the Haber Process

A

N2 + 3H2 = 2NH3 (exo)

450C, 200-1000atm, iron catalyst

19
Q

Outline the Contact Process

A

1) S(s) + O2(g) > SO2(g)
2) SO2(g) + 0.5O2(g) = SO3(g) (exo)

450C, 10atm, V2O5 catalyst

20
Q

Outline the production of methanol from CO

A

CO(g) +2H2)g) = CH3OH (exo)

400C, 50atm, chromium and zinc oxide catalysts

21
Q

Outline the hydration of ethene to produce ethanol

A

C2H4(g) + H2O(g) = CH3CH2OH(l) (exo)

300C, 70atm, Concentrated H3PO4 catalyst

22
Q

Where mA + nB = pC + qD

write the formula for Kc

A

Kc = ([C]^p x [D]^q) / ([A]^m x [B]^n

23
Q

Moles of reactant @ equilibrium =

Moles of product @ equilibrium =

A

initial moles - moles reacted

initial moles + moles formed

24
Q

What does Kc show?

A

Larger Kc values = greater amount of product

Small Kc values = equilibrium favours reactants

25
Q

What condition affects Kc?

A

Temperature

26
Q

Outline the steps to a method for calculating an equilibrium constant (Kc)

A
  1. Prepare an equilibrium mixture
  2. Titrate the equilibrium mixture
  3. Work out the initial moles of reactants
  4. Work out the equilibrium moles of acid (from the titre results)
  5. Calculate the equilibrium amount of moles from other substances
  6. Calculate the equilibrium constant (Kc)

AS CHEMISTRY (17 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions