calcium chloride +
carbon dioxide + water.HCl(aq) + CaCO3(s)
CaCl2(aq)
+ CO2(g)
+ H2O(l)gcsescience.com 3 gcsescience.com
Measuring the Rate.
The rate of a reaction
may be measured by following
the loss of a reactant,
or the formation of a product.
Three
of the reactions
which may be studied
to show how the rate can be changed
are shown below.
They are
1) The reaction
between calcium carbonate
and dilute hydrochloric acid.
2) The reaction between
sodium thiosulphate
solution and hydrochloric acid.
3) The decomposition of
hydrogen peroxide
solution.
1) The reaction
between calcium carbonate
and dilute hydrochloric acid.
HCl + calcium
carbonate
calcium chloride +
carbon dioxide + water.
HCl(aq)
+ CaCO3(s)
CaCl2(aq)
+ CO2(g)
+ H2O(l)
The rate of this reaction
can be measured
by following the rate at which carbon
dioxide is formed.
This can be done by conducting the reaction
in an open flask on an electric
balance (weighing machine).
As the carbon dioxide escapes to the air,
the mass of the flask
will decrease.
You can take a reading from the balance
every 30 seconds,
then plot a graph of loss
of mass
against time.
The gradient of the plot
(the steepness of the slope)
shows the rate of the reaction
(how fast it is going).
See increasing the surface area.
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Copyright © 2007 Dr. Colin France. All Rights Reserved.
