Topic 6 (The Rate & Extent of Chemical Change) Flashcards
Rate of reaction equation
Rate of Reaction = Quantity of reactants formed/ Time Taken
Rate of Reaction = Quantity of reactants used/ Time taken
Main way Mass and Volume are measured for Rate of Reaction
Mass = Grams
Volume = cm^3
All ways measured for rate of reaction
Mole, Grams, cm^3, Dm^3, per minute
Explain a Rate of reaction graph for reactants
Decreases at an decelarating rate since at the start more reactants so high amount of collisions then decreases
What factors effect rate of reaction
- Temperature
- Surface Area
- Concentration
- Pressure
- Catalyst
Explain rate of reactants for volume of Gas produced
Increases at a decelerating rate since
What is Collison Theory
For Particles to react they need to collide with each over with sufficient energy
Factors in Collison Theory
1) Amount of energy particles have the more energy they can transfer during collision
2) Frequency of Collisions
how often particles collide - since not all collisions are successful more collisions produce more successful collisions increasing ROR
How does Temperature effect Rates of Reaction
When temperature increases particles gain more energy
This makes them move faster
This means they collide more frequently and collide with more energy so more likely to exceed activation energy
This creates a overall higher Rate of Reaction
How does concentration/pressure effect rate of reaction
Means how many particles there are per unit of volume
Concentration refers to solutions and Pressure gas
Higher conc/pressure means more particles per unit of volume
Making collisions more frequent
increasing Rate of Reaction
How does surface area effect rate of reaction
Higher surface area to volume ratio means there is a larger area so there will be a higher frequency of collisions
Increasing Rate of Reaction
What is a Catalyst
Catalyst speed up rates of reactions without being used up (not included in reaction since not used up)
How do Catalyst effect rate of reaction
It provides an alternative pathway with lower activation energy.
Reducing ROR
Why are catalysts important in industry?
They reduce energy costs and increase efficiency
Give an example of a biological catalyst.
Ezymes (e.g., amylase, catalase).
Name a catalyst used in the Haber process.
Iron (Fe) speeds up ammonia production.
How do you calculate the rate of reaction from a graph?
Rate = change in quantity ÷ time (e.g., mass lost, volume of gas produced).
How do you find the rate at a specific time?
Draw a tangent to the curve at that point and calculate its gradient.
What happens to the gradient as the reaction progresses?
It decreases as reactants are used up and the reaction slows.
