Zusammenfassung der Ressource
Rates of Reaction:
- Amount of product made or the amount
of reactant used up per unit time
- Changing the rate of reaction
- Temperature
- Heating reactants means
particles move fas
- Increasing frequency of collisions, more successful
collisions (reactions happen) rate of reaction increases.
- Concentration
- The higher the concentration, the more particles so more frequent collisions, resulting in a higher
the rate of the chemical reaction.
- Particle size
- The smaller the particle size, the larger the
surface area, and the higher the rate of reaction.
- Catalysts
- Catalysts can speed up the rate of reaction
without being used up themselves. However
they are specific (only speed up) a certain
reaction.
- Industrial processes that use a catalyst
- Cracking long hydrocarbon chains: use porcelain chips or aluminium
oxide as the catalyst
- Hydrogenation of unsaturated plaint oils (making
margarine): use nickel as the catalyst
- Catalytic converter in cars: use platinum
and other metals as the catalyst
- Exothermic reactions
- Exothermic reactions give out energy, mainly in the
form of heat, to the surroundings.
- Examples of exothermic
reactions
- Neutralisation reactions, Displacement reactions,
Combustion (burning) reactions
- Collision theory
- For a reaction to occur, particles need to collide
with the particles from the other reactants in the
right orientation and with enough energy to
overcome the activation energy.
- Increasing the rate of reaction means there are more
frequent collisions. Increasing temperature also means
there are more successful collisions.
- Increasing the rate of reaction
- Stir it, increase temperature of liquid,
smaller solid pieces (even powdered) as it
creates a larger surface area , use a
catalysts ,Increase concentration of liquid