C8 - Rates of Reaction

Question 1

What is the general equation for reversible reactions?

Answer 1

A + B ⇌ C + D

Question 2

What is the balanced symbol equation for the Haber process?

Answer 2

N2 + 3H2 ⇌ 2NH3

Question 3

What is 2NH3?

Answer 3

ammonia

Question 4

What can we uses ammonia for?

Answer 4

nitrogen based fertilisers

Question 5

What is a source of nitrogen?

Answer 5

can be extracted from air

Question 6

What is a source of hydrogen?

Answer 6

produced by reacting methane with steam

Question 7

How is ammonia formed?

Answer 7

Purified nitrogen & hydrogen passed over iron catalyst at around 450° & 200 ATM pressure

Question 8

How can we increase the yield of ammonia?

Answer 8

cool it down & convert to a liquid which is removed

Question 9

What happens to the mixture of unreacted gases (hydrogen & nitrogen) ?

Answer 9

recycled back over catalyst

Question 10

What is the symbol indicating a reversible reaction?

Answer 10

⇌

Question 11

What happens if you heat hydrated copper sulfate (blue) ?

Answer 11

reacts & forms anhydrous copper sulfate (white) & produces water

Question 12

What happens if a reversible reaction happens in a closed system? What is this called?

Answer 12

causes the forwards & backwards reactions to happen at exactly the same rate = dynamic equilibrium

Question 13

What is the equation for rates of reaction?

Answer 13

chnge in reactnt (or prdct)/ time

Question 14

What is Le Chatelier’s principle?

Answer 14

position equillbrm. will shift to oppose external changes

Question 15

What is the effect of increasing the concentration of reactants on a reaction at dynamic equillibrium?

Answer 15

favours forwards reaction

Question 16

What is the effect of decreasing the concentration of products on a reaction at dynamic equillibrium?

Answer 16

favours forwards reaction

Question 17

What is the effect of increasing pressure on a reaction at dynamic equillibrium?

Answer 17

favours reaction that leads to fewst. molecules

Question 18

What is the effect of decreasing pressure on a reaction at dynamic equillibrium?

Answer 18

favours reaction that leads to mst molecules

Question 19

What is the effect of increasing temperature on a reaction at dynamic equillibrium?

Answer 19

favours endo. reaction

Question 20

What is effect of decreasing temperature on a reaction at dynamic equillibrium?

Answer 20

favours exo. reaction

Question 21

What 2 things must particles have to react?

Answer 21

actvtn enrgy & collisions

Question 22

If you increase the temperature of a reaction, how does it affect the RoR?

Answer 22

• ↑ RoR
• particles gain thrml enrgy
• more particles have actvtn enrgy
• move faster & have more frqunt cllsns

Question 23

If you increase the concentration, how does it affect the RoR?

Answer 23

• ↑ RoR
• more particles there are in crtn volume = more frquntly particles will collide

Question 24

If you increase the surface area, how does it affect the RoR?

Answer 24

• ↑ RoR
• more reactant particles are exposed = more frqunt collisions

Question 25

How do catalysts affect RoR?

Answer 25

• ↑ RoR
• reduces actvtn enrgy
• finds altnrtv pthwy for reaction to take requiring less enrgy

Question 26

If you increase the pressure, how does this affect the RoR?

Answer 26

• ↑ RoR
• more GAS particles in certain volume = more frquntly GAS particles will collide