An investigation into how concentration affects the rate of a chemical reaction

... create a slight margin of error because some of the water was displaced when doing this although it was very little. Then we clamped the measuring cylinder in place. We changed the size of the cylinders, however, this did not make the test unfair. We then put the delivery tube under the cylinder so the air from the experiment could displace the water. To make sure the volumes of acid and water were right we now measured the volumes of each in a measuring cylinder to be accurate. To make sure the mass of marble chips were right we measured on the electronic balance to one decimal place. Then we put the chips and the acid in the conical flask and started the stopwatch.

As the experiment has started we now recorded the volume of gas every twenty seconds. We did this until two minutes had elapsed. We then changed the mass of the chips and the concentration of acid until we had all the data that was required. While doing this experiment we had to work carefully to avoid accidents and follow safety procedures.

Underneath is a diagram of how the experiment was set-up

To find out information for my investigation I used the resources listed below.

Internet- www.about.com

www.excite.co.uk

Books- Nelson Science

Collins science Obtaining evidence

While working all safety procedures were followed very carefully like the use of safety goggles and putting the bags under the table. The measurements I feel were fairly accurate as the results were what was expected. There was one anomalous result, however, which was repeated to get a more accurate result. We repeated the experiment three times so we could find averages and get more accurate results. The results were measured to the nearest centimetre cubed because this was the maximum accuracy of the cylinders. The results show the results we got for each experiment.

Experiment No

Concentration

Cm³

Concentration Molars Time (seconds) of when volume of

Carbon dioxide (Cm³) was recorded

Acid

Water

20

40

60

80

100

120

1

25

0

2

50

140

160

200

240

270 ...