Zusammenfassung der Ressource
Chemistry Rates of Reaction Revision
- Measuring rates of reaction
- The rate of
reaction can be
measured by
considering the
amount of
product formed
or reactant used
in a given period
of time
- The rate of
reaction
changes
depending on
how far
through the
reaction is!
- The
activation
energy is
the
minimum
amount
of energy
needed
for a
reaction
to occur.
- Gas produced?
measure with gas
syringe, burette
or upside down
measuring
cylinder
- Solid
produced?
measure
with balance
- The rate of
an equation
decreases
with time.
This is
because the
reactants are
used up,
resulting in
fewer
collisions.
- The rate of
reaction
increases if the
temperature is
raised. This is because:
- The reactant particles
move more quickly,
they have more kinetic
energy
- This means they move faster,
which increases collision
frequency
- More
collisions=faster
reaction rate
- Rate of reaction increases if pressure or concentration is increased.
- Particles become
more crowded, so
collisions are more
frequent
- Rate of reaction increases.
- Increasing the
concentration of a
reactant increases the
rate of reaction.
- Reactant particles become more crowded and
there is a greater chance of collision.
- rate of reaction = amount of reactant used or product formed
- Surface area increases the rate of reaction.
- More particles are exposed to the reactant.
- Greater chance of collision, rate increases.
- Catalysts increase the rate of reaction without being used up.
- They lower the activation energy needed, so more collisions result in a reaction.
- Lower costs - less energy is needed.
- The rate of reaction is the speed at which a reaction happens.
- Collision theory - reactant particles must collide with activation energy for reaction to occur.