Equilibrium UNIT 2

Question 0

What happens if you increase the pressure in an eqm reaction

Answer 0

The eqm will shift to the side with fewer particles

Question 1

Le Chateliers principle

Answer 1

If you change the pressure, concentration or temperature of an eqm reaction the position of the eqm will shift to reduce this change

Question 2

What happens if you increase the temperature of an eqm reaction

Answer 2

Means adding heat. The eqm shifts in endothermic direction to absorb this heat

Question 3

If you increase the concentration of one of the reactants in the eqm reaction

Answer 3

Eqm will shift in opposite direction to reduce this increase

Question 4

When you increase the concentration of acid in an eqm reaction

Answer 4

The eqm will shift to the right

Question 5

When you increase the concentration of the alkali in an eqm reaction

Answer 5

The eqm shifts to the left

Question 6

Conditions for making ammonia

Answer 6

Temp…..450c
Pressure….200 atm
Catalyst…..iron

Question 7

Conditions for making methanol using the high pressure process

Answer 7

Temp….650-720k
Pressure….200-350 atm
Catalyst…. Mixture of zinc and chromium oxides

Question 8

Conditions for making methanol using lower pressure process

Answer 8

Temp….450-570k
Pressure… 40-100 atm
Catalyst….copper based

Question 9

What happens if you decrease the temperature on an eqm reaction

Answer 9

Means removes heat. The eqm shifts in exothermic direction to try to replace the heat

Question 10

Ethanol can be formed from……

Answer 10

Ethene and steam.

Question 11

Conditions for making ethanol

Answer 11

Temp…..300c
Pressure…….60-70 atm
Catalyst……..phosphoric acid

Question 12

What are the Compromise conditions for producing ethanol

Answer 12

The forward reaction is exothermic, so lower temps are used to favour forward reaction. But lower temps mean slower rate of reaction so 300c is a compromise between maximum yield and faster reaction. High pressure favours forward reaction, also increases rate of reaction. High pressures are expensive as stronger pipes and containers are needed to withstand the pressure. Also increasing the pressure can cause side reactions to occur , so 60-70 atm is compromise between maximum yield and expense. (All comes down to minimising cost)

Question 13

What happens to the unreacted ethene during the process of making ethanol

Answer 13

Only a small proportion of ethene reacts each time the gases pass through the catalyst. To save money and raw materials, the unreacted ethene is separated from the liquid ethanol and recycled back into the reactor. Means around 95% of the ethene is eventually converted to ethanol

Question 14

Methanol is produced from….

Answer 14

Hydrogen and carbon monoxide

Question 15

Methanol and methanol can used….

Answer 15

As fuels for cars, either on their own or added to petrol. They are both thought to be greener than petrol, they can be made form renewable resources and they produce fewer pollutants. They can both be carbon neutral fuels

Question 16

What does carbon neutral mean

Answer 16

Something that has no net annual carbon emissions to the atmosphere