2.3 Rates of Reaction Flashcards
what is the equation for the rate of a reaction and what units are used?
Rate = 1/time unit = s^-1
what can we do to increase reliability?
repeat the experiment
if a gas is produced, how can we measure the rate of reaction?
give two example reactions.
the volume of gas produced or the mass of gas lost can be measured over a period of time.
metal + acid -> salt + hydrogen
carbonate + acid -> salt + water + carbon dioxide
if a ppt forms, how can we measure the rate of reaction?
give one example reaction
the time it takes for the ppt to form can be measured
sodium thiosulfate with acid
what is the activation energy?
the minimum amount of energy needed for particles to react
what is collision theory (when do particles react)
reactions take place when particles collide with a certain amount of energy
what factors affect the rate of a reaction? x4
- temperature
- concentration
- surface area
- catalyst
what factors affect the rate of a reaction? x4
- temperature
- concentration
- surface area
- catalyst
explain the cause of a temperature increase on the rate of a reaction and explain why it happens.
- increase in temperature causes an increase in the
rate of reaction
why: - particles have more energy
- particles collide more often
- more successful collisions per second
explain the cause of a concentration increase on the rate of a reaction and explain why it happens.
- increasing concentration increases rate of reaction
why: - more particles in the same volume
- more collisions
- more successful collisions per second
explain how surface area can affect the rate of a reaction.
- the smaller the particle, the greater the surface area
- more collisions
- more successful collisions per second
what is a catalyst?
a substance that speeds up a reaction without getting used up
how does a catalyst work?
they provide an alternate reaction pathway of lower activation energy. this leads to more successful collisions per second.
