3.3 Concentration and Rate

1
3.3 Concentration and Rate

• LO I understand how to calculate and compare the
  rate of a reaction.

2
Aim

• To find out how varying the concentration of
  iodide ions affects the rate of reaction with
  hydrogen peroxide.

About the reaction
H2O2(l) 2H(aq) 2I-(aq) I2(aq) H2O(l)
The concentration of the iodide ions was varied
by changing the proportions of water and iodide
solution while keeping the total volume constant.
The end point of the reaction is when the first
hint of the blue/black colour appears.
LO I understand how to calculate and compare the
rate of a reaction.
3
Calculating the rate
1

• Relative rate

t
Where,

• t time in seconds (s)

• Relative rate is in reciprocal seconds (s-1)

Conclusion
The higher the concentration of the iodidie ions,
the the rate of the reaction with
hydrogen peroxide.
faster
LO I understand how to calculate and compare the
rate of a reaction.