T8 YR11 - Rates of reaction Flashcards
How do you calculate rate?
Something per unit / time
How can you see the rate of reaction in 2 ways?
Dissapearance of reactant
Appearance of product
What is one method to measure the appearance of a product?
Gas syringe to measure the hydrogen escaping
What is the collision theory?
To increase surface area
Exposes more particles to other reactant
Increases frequency of collisions
Increases successful amount of collisions
Increases rate of reaction
NEEDS ACTIVATION ENERGY
What is another way of increasing amount of successful collision?
Temperate increase
How does a higher concentration affect the rate of reaction?
More particles are available to collide with each other meaning more successful collision and a increases rate of reaction
What does the effect of pressure have on the rate of reaction?
Increased pressure pushes particles closer together meaning more dense and more collisions
Are transition metals good catalysts?
Yes
What forms can transition metals come in to increase surface area?
Powder, pellets and fine gauze
Do catalysts have anything to do with collisions?
No
Why are catalysts not linked with amount of collisions?
Provide an alternative reaction pathway with a lower activation energy
What are reversible reactions?
E.G. acid - alkali
Endo and exothermic reactions can affect reversible reactions
If forward reaction is exothermic what is the backward reaction?
Endothermic
What is dynamic equilibrium?
Equal however the reaction is still occurring
What is the Le Chateler principle?
Position of equilibrium will change in order to cancel the change made
What is the altering condition for pressure?
Increase in pressure favours the side of the reaction with the least number of moles
What is the altering condition for temperature?
Increase in temperature increases both rates of reaction, favours endothermic. Decrease temp favours exothermic reaction
What is the acronym for temperature altering conditions?
TINENDO - temp inc favours endothermic
