Brainscape's Knowledge GenomeTM

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


See full index

Chemistry > Equilibria > Flashcards

Equilibria Flashcards

1
Q

What is a dynamic equilibrium?

A

A situation in which the composition of a constant concentration reaction mixture does not change because both forward and backward reactions are proceeding at the same rate and continuously.

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

What is ammonia used to make?

A

Mostly fertilisers like ammonium, nitrate, ammonium sulphate and urea.
Also synthetic fibres, dyes, explosives and plastics (polyurethane).

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

What process is used to make ammonia?

A

The Haber process.

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

What raw materials are used in the Haber process?

A

Air - provides N2

Water and natural gas (CH4) - provides H2

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

What conditions are used in the Haber process?

A

Pressure - 20,000 KPa (200 atmospheres)

Temperature - 670K

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

How is ammonia made?

A

Nitrogen and hydrogen are fed into a converter with a ratio of 1:3 and is passed over an iron catalyst (lumpy).
Any left over N2 or H2 is fed back into the converter.

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

Why is the iron catalyst used in the Haber process replaced every 5 years?

A

It gets poisoned due to impurities in the gas stream.

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

How is ethanol made?

A

Fermentation of sugars like glucose, using yeast as a catalyst.

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

Give the equation which shows the production of ethanol.

A

C6H12O6(aq) –yeast–> 2C5H5OH(aq) + CO2(g)

Glucose Ethanol

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

What is ethanol used for?

A

Alcohol, cosmetics, drugs, detergents, inks and motor fuels.

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

How is ethene obtained from crude oil?

A

Fractional distillation and then cracking.

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

What catalyst is used in the production of ethanol from ethene?

A

Phosphoric acid catalyst absorbed on silica.

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

Show the reversible reaction for the production of ethanol.

A

H2C=CH2(g) + H2O(g) 🔄 CH3CH2OH(g) 🔼H*=-46KJmol-

Ethene Ethanol

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

What conditions are used in the production of ethanol?

A

Pressure - 6500 KPa

Temperature - 570K

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

What are the problems with applying Le Châteliers principle to achieve a maximum yield in the reversible reaction for the production of ethanol?

A
  • high pressure causes polymerisation if ethene, it is also expensive
  • Low temperature causes a slow rate of reaction
  • Too much steam dilutes the catalyst
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What conditions are used in the production of Methanol?

A

Pressure - 1000kPa
Temperature - 500K
Catalyst - Copper

17
Q

What is methanol used for?

A

Starting materials for chemical feedstock
Manufacture of methanal (formaldehyde)
Motor fuel

18
Q

Why is methanol used as a motor fuel?

A

Methanol fires can be extinguished using water.

19
Q

What is methanol made from?

A

Carbon monoxide and hydrogen using a copper catalyst.

20
Q

What’s the symbol equation for the production of methanol?

A

CO(g) + 2H2(g) 🔄 CH3OH(g) 🔼H*=-91kJmol-1

21
Q

What changes Kc?

A

Temperature

22
Q

What conditions are used in the production of ethanol?

A

Temperature: 570K
Pressure: 6500kPa

23
Q

What is methanol commonly used for?

A

Starting material for chemical foodstock

Used to make methanal (formaldehyde)

24
Q

Why is methanol a good motor fuel?

A

Methanol fires can be put out with water, so they’re safer for cars.

25
Q

What raw materials are used to make methanol?

A

Carbon monoxide

Hydrogen

26
Q

What’s the reaction for the reversible reaction of methanol?

A

CO(g) + 2H2(g) 🔄 CH3OH(g) 🔼H* = -91kJmol-1

27
Q

What conditions are used to produce methanol?

A

Temperature: 500K
Pressure: 10 000kPa
Copper catalyst

28
Q

What conditions are required for the fermentation of ethanol?

A

Temperature: 37-40*C
Must be in the presence of oxygen
To enable enzymes in yeast to work

29
Q

What is an equilibrium mixture?

A

The mixture of reactants and products formed when a reversible reaction is allowed to proceed in a closed container until no further change occurs.

30
Q

What is Le Châteliers principle?

A

If a system at equilibrium is disturbed, the equilibrium move in the direction that tends to reduce the disturbance.

Chemistry (22 decks)

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