Rates Of Reaction Flashcards
What is the definition of a catalyst?
Substance which increases the rate of a chemical reaction without being used up in the process
How does concentration/pressure affect ROR?
Increase the pressure/conc. More particles in the same volume therefore more frequent successful collisions. Increases rate
How does a catalyst work?
Lowers the activation energy
What is a homogeneous catalyst?
Catalysts and reactants are in the same physical state
What’s a heterogeneous catalyst?
Has different physical state to the reactants
What are the three stages of heterogeneous?
Adsorption of the reactants to surface of catalysts
Bonds break and reaction happens
Desorption of products
Three environmental effects of catalysts
Low reaction temperatures can be used reducing demand for fossil fuels and reducing CO2
Different reactions can be used with better atom economy and less waste
Catalytic converters reduce emissions from car exhaust
What are the economic effects of catalysts?
They are used in industries where the product is in great demand and commands a high price
They are incorporated in luxury good to comply with legislations on emissions
How do you measure the volume of gas?
Connecting bung
Measure the change in water level against time taken
Define rate of reaction reaction?
The change in concentration of a reactant or a product in a given time
What is the effect of changing temperature on the Bolzmann distribution curves?
Bigger area under line. At a higher temperature more molecules with at least the activation energy. More frequent successful collision do faster rate of reaction
How does temperature affect ROR?
Particles gain more kinetic energy resulting in more frequent successful collisions. Faster rate of reaction
What is the effect of catalyst on Bolzmann Distribution curve
There is more area under the line. More molecules have at least the activation energy do more frequent successful collisions so faster rate of reactions
