Equilibria

Question 1

What are two conditions for a reversible reaction in a closed system to be in equilibrium?

Answer 1

1. rate of forward reaction = rate of reverse reaction
2. concentrations of products and reactants no longer changing

Question 2

State the symbol equation for the production of ammonia in the Haber process. Include state symbols.

Answer 2

N2 (g) + 3H2 (g) <-> 2NH3 (g)

Question 3

What are the typical conditions in the Haber process?

Answer 3

• 450 degrees C
• 200 atm (or 20 000 kPa)
• iron catalyst

Question 4

State the symbol equation for the conversion of sulfur dioxide to sulfur trioxide in the Contact process. Include state symbols.

Answer 4

2SO2 (g) + O2 (g) <-> 2SO3 (g)

Question 5

What is the following equation?
N2 (g) + 3H2 (g) <-> 2NH3

Answer 5

production of ammonia in Haber process

Question 6

What is the following equation?
2SO2 (g) + O2 (g) <-> 2SO3 (g)

Answer 6

conversion of sulfur dioxide to sulfur trioxide in the Contact process

Question 7

What are the typical conditions in the Contact process, to convert sulfur dioxide into sulfur trioxide?

Answer 7

• 450 degrees C
• 2 atm
• vanadium pentoxide catalyst

Question 8

What is the source of hydrogen in the Haber process?

Answer 8

methane

Question 9

What is the source of nitrogen in the Haber process?

Answer 9

air

Question 10

What is the source of sulfur dioxide in the Contact process?

Answer 10

burning sulfur or roasting sulfide ores

Question 11

What is the source of oxygen in the Contact process?

Answer 11

air

Question 12

What are some substances used as fertilisers?

Answer 12

-ammonium salts and nitrates
-nitrogen
-phosphorus
-potassium

Question 13

What can ammonium salts be used for?

Answer 13

fertiliser

Question 14

What can nitrates be used for?

Answer 14

fertiliser

Question 15

What do NPK fertilisers do?

Answer 15

provide nitrogen, phosphorus and potassium for improved plant growth

Question 16

what happens when hydrated cobalt(II) chloride is heated

Answer 16

it loses its water of crystallisation and turns into anhydrous cobalt(II) chloride

Question 17

what happens when anhydrous blue cobalt(II) chloride crystals are added to water

Answer 17

turns pink

Question 18

what happens when anhydrous copper(II) sulphate is added to water

Answer 18

turns blue

Question 19

what happens when you increase concentration in a reversible reaction?

Answer 19

favor forward reaction

Question 20

what happens when you decrease concentration in a reversible reaction?

Answer 20

favor reverse reaction

Question 21

what happens when you increase temperature in a reversible reaction?

Answer 21

favor the endothermic reaction

Question 22

what happens when you decrease temperature in a reversible reaction?

Answer 22

favor exothermic reaction

Question 23

what happens when you increase pressure in a reversible reaction?

Answer 23

favor side with less moles

Question 24

what happens when you decrease pressure in a reversible reaction?

Answer 24

favor side with more moles

Question 25

what happens when you decrease or increase a catalyst in a reversible reaction?

Answer 25

rate of reaction increase but there is no effect on the actual equilibrium