2. Rates of Reaction Flashcards
(13 cards)
What is collision theory?
In order to undergo a chemical reaction particles must collide with each other particles must also collide with sufficient energy.
A successful collision is when ______ is fulfilled?
The activation energy
What are the three things you can do to increase the rate of reaction?
- Increase the frequency of collisions between particles
- Give the particles more energy
- Add a catalyst
What are the five factors that affect the rate of a chemical reaction?
- Surface area of solid reactants
- Concentration of dissolved
- Pressure of gases
- Temperature
5.Catalyst
What would an accurate way to measure reaction rates?
With a timer and a gas syringe, measuring how much gas is produced in a given time.
What increasing the surface area of a solid do to the reaction?
Increases the rate of reaction as there is a greater surface area where solid particles collide and therefore there are more frequent collisions between particles.
What effect does increasing the concentration of dissolved reactants have on the rate and why?
Higher concentration = more particles in the same volume which means thatthere will be more successful collisions.
What does increasing the pressure of a gaseous reactant do to the rate of reaction?
Increases the rate of reaction as there is the same amount of particles in a smaller volume which makes them collide more.
Why does increasing the temperature increase the rate of reaction?
Particles have more energy so they can move around faster so there are more frequent collisions between particles. This means more collisions occur with energy greater or equal to the activation energy so there are more are more frequent successful collisions.
What is a catalyst?
A substance which increases the rate of reaction whilst being chemically unchanged at the end of the reaction.
How can you show that a solid is a catalyst?
If the solid’s mass is unchanged at the end if the experiment then it is a catalyst.
How do catalysts work?
They provide an alternative route for the reaction with a lower activation energy.
Why are catalysts important?
They increase the rate of reaction without being used up which means that they can be used many times. They allow reactions to be carried out at lower temperatures and pressures which saves money and energy.
