Rates of Reactions Flashcards
What is collision theory?
Reactions happen when particles collide with enough energy.
What factors effect the rate of a reaction?
- Temperature
- Concentration/pressure
- Surface area
- Catalyst
How do you calculate rate of reaction?
Reactant used or product formed / time
How does surface area to volume ratio effect the rate of reaction?
Large surface area to volume ratio increases rate of reaction
This is because it increases the chance of collisions.
Why does an increased temperature increase the rate of reaction?
It gives the particles more energy so they move faster so they collide more often with more energy.
Why does higher concentration increase the rate of reaction?
There are more particles in the same area so they are more likely to collide.
What are catalysts?
Substances that increase the rate of a reaction by providing an alternative energy pathway with a lower activation energy.
What catalyst is used in catalytic converters?
Platinum
What is the reaction that takes place in catalytic converters?
Carbon monoxide and nitrogen oxide are converted to carbon dioxide and nitrogen.
What catalyst is used in the hydrogenation of vegetable oil to form margarine?
Nickel
What catalyst is used in the Haber process?
Iron
What is a reversible reaction?
A reaction where the products can be converted back into reactants.
What are 2 examples of reversible reactions?
- Decomposition of ammonium chloride
- Dehydration of copper sulfate
What is Le Chatelier’s principle?
If a system at equilibrium is subjected to a change, the system will readjust itself to counteract the applied change.
How can the rates of reversible reactions be changed from the equilibrium?
- Changing concentration (adding/removing products/reactants)
- Changing temperature
- Changing pressure of gasses
