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Flashcards in Rate Of Reaction Deck (15)
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1
Q

What is the rate of a chemical reaction?

A

How fast the reactants are turned into products

2
Q

What is the calculation for the rate of reaction?

A

amount of reactant used or amount of product formed

time

units: g/s or cm3/s

3
Q

How can rate of reaction be measured?

A
  • Mass of reaction mixture
  • Volume of gas given off
  • Light transmitted through solution

→ measures changes over time “quantative data”

→ cross method is subjective

4
Q

What are the five things that affect the rate of reaction?

A
  • concentration of solutions
  • pressure of gas
  • temperature
  • surface area (of solids)
  • catalysts (ish)
5
Q

Describe the collision theory

A

Reactions only take place when the particles that make up the reactants collide with enough energy

6
Q

What is activation energy?

A

the minimum amount of energy that particles must have when they collide before they can react

7
Q

How does a higher concentration of a solution increase the rate of reaction?

A

There are more particles in the same volume to react with so there is an increased collisioin frequency

8
Q

How does incresing the pressure of the reactants in a gas reaction increase the reaction rate?

A

It squashed the gas particles closer together so there are more particles in the given vollume, causing an increased collision frequency

9
Q

How does a larger surface area increase the rate of reaction?

A

There are more of the reactant particles exposed to react with so there is a greater collision frequency

10
Q

How does a higher temperature increase the rate of reaction?

A
  • Greater collision frequency → more energy = move faster
  • More successful collisions → more particles have required activation energy
11
Q

What is a catalyst?

A

A catalyst is a substance that increases the rate of a reaction without being chemically changed or used up by the end of the reaction

12
Q

How does a catalyst increase the rate of reaction?

A

It provides an alternate pathway for a reaction that has a lower activation energy. Thus more particles have the required EA for a successful collsion

13
Q

How do catalysts help reduce costs in industrial reactions?

A
  • Lower temperautre → less fossil fuels used
  • Small amount used, doesn’t get used up
  • Higher yield per unit time → increased productivity
14
Q

What are some disadvantages of using a catalyst in an industrial process?

A
  • Expensive
  • Specific → different reactions need different catalysts
  • Need to be regularly cleaned
15
Q

(opt) Give some examples of catalysts

A
  • Iron → Haber Process, produces ammonia
  • Nickel → hydrogenation of oils, forms margarine
  • Platinum → car catalytic convertors, produces CO2, N2 and water vapour