The aim of this experiment is to find out how different variables affect the rate at which the reaction between Marble chips (CaCO ) and
Hydrochloric acid (HCl) takes place. There are many variables that affect the rate of this reaction such as the following:
1. Temperature
2. Concentration (Pressure for gases)
3. Catalyst
4. Surface area
Materials:
5.00 g of Marble chips
2M HCl
1M HCl
Balance pan
Weight scale
200ml conical flask
Residue container
50ml beaker
Timer/ stop watch
Cotton wool plug
Measuring cylinder
Method:
1. Using a measuring cylinder, pour 30 ml 2.0 M HCl into a 50ml beaker.
2. Weight approximately 5 g large coarse marble chips into a 250ml conical flask and loosely place a cotton wool plug in the neck of the flask. Record mass accurately.
3. Place the conical flask and the beaker of acid on the balance pan so that it is reading total assembled mass.
4. Carefully and quickly remove the cotton wool plug, add the acid to the flask, replace the beaker on the balance pan beside the flask, and replace the plug. Immediately start a stop watch.
5. Note the reading on the balance at 15 second intervals. Continue up to 5 minutes, ending when four consecutive readings are constant.
6. Repeat the experiment as described above:
Part 2 - using 5g of fine ground marble chips and 30ml 2M acid
Part 3 – using coarse ground marble chips and 30ml 1M acid
Risk(s):
The risks involved in this experiment is the 1M and 2M HCl as they are corrosive, harmful by inhalation, can cause burns and have a risk of serious damage to the eyes. To protect yourself from these risks you must wear safety glasses, lab coat of appropriate size and length and gloves.
Results:
Part 1
Part 2
Part 3
Mass Marble Chips
5.00g
4.99g
5.01g
Total system mass
198.72g
196.62g
223.92g
0.25 min
198.67g
196.56g
223.90g
0.50 min
198.62g
196.47g
223.89g
0.75 min
198.57g
196.39g
223.86g
1.00 min
198.52g
196.31g
223.83g
1.25 min
198.48g
196.24g
223.81g
1.50 min
198.43g
196.18g
223.78g
1.75 min
198.39g
196.12g
223.76g
2.00 min
198.34g
196.07g
223.74g
2.25 min
198.30g
196.03g
223.72g
2.50 min
198.27g
195.99g
223.70g
2.75 min
198.23g
195.96g
223.68g
3.00 min
198.20g
195.93g
223.66g
3.25 min
198.17g
195.91g
223.65g
3.50 min
198.14g
195.89g
223.63g
3.75 min
198.12g
195.87g
223.61g
4.00 min
198.09g
195.86g
223.60g
4.25 min
198.07g
195.85g
223.59g
4.50 min
198.05g
195.83g
223.58g
4.75 min
198.04g
195.83g
223.57g
5.00 min
198.02g
195.82g
223.56g
Part 1:
Time (min)
Mass (g)
Mass Loss(g)
0
198.72
0
0.25
198.67
0.05
0.5
198.62
0.1
0.75
198.57
0.15
1
198.52
0.2
1.25
198.48
0.24
1.5
198.43
0.29
1.75
198.39
0.33
2
198.34
0.38
2.25
198.3
0.42
2.5
198.27
0.45
2.75
198.23
0.49
3
198.2
0.52
3.25
198.17
0.55
3.5
198.14
0.58
3.75
198.12
0.6
4
198.09
0.63
4.25
198.07
0.65
4.5
198.05
0.67
4.75
198.04
0.68
5
198.02
0.7
Part 2:
Time (min)
Mass (g)
Mass Loss(g)
0
196.62
0
0.25
196.56
0.06
0.5
196.47
0.15
0.75
196.39
0.23
1
196.31
0.31
1.25
196.24
0.38
1.5
196.18
0.44
1.75
196.12
0.5
2
196.07
0.55
2.25
196.03
0.59
2.5
195.99
0.63
2.75
195.96
0.66
3
195.93
0.69
3.25
195.91
0.71
3.5
195.89
0.73
3.75
195.87
0.75
4
195.86
0.76
4.25
195.85
0.77
4.5
195.83
0.79
4.75
195.83
0.79
5
195.82
0.8
Part 3:
Time (min)
Mass (g)
Mass Loss(g)
0
223.92
0
0.25
223.9
0.02
0.5
223.89
0.03
0.75
223.86
0.06
1
223.83
0.09
1.25
223.81
0.11