Chemistry practical
Clare Chong
P2
!
!
!
!
!
Chemistry Practical 4: Measuring rate of reaction
Aim of experiment:
To determine the rate of reaction when the concentration of I2 increases.
!
!
!
Chemical equation:
2Fe3+ + 2I- --> 2Fe2+ + I2
!
!
!
Apparatus & materials:
Apparatus
Quantity
50ml Pipette
1
10ml Pipette
1
Pipette bulb
1
100ml beaker
2
50ml Burette
1
250ml Conical Flask
6
Timer
1
Distilled water
100ml or more
50ml Measuring Cylinder
1
Bottle of starch
1
S2O32-
100ml or more
Fe3+
50ml or more
I-
50ml or more
!
!
!
Procedure:
! pipette 50ml of 0.02M Kl, 50ml of 0.02M Fe3+ into separate beakers.
1.
2. Prepare S2O32- solution in a burette.
3. Pour I- and Fe3+ solution into a conical flask. Start the timer.
4. For every 5 minutes, pipette 10ml of solution mixture into a flask, and 10ml of distilled water to quench the solution.
5. Add 3 drops of starch to the solution.
6. Then, proceed to titrate with S2O32-.
7. The solution will change from blue-black to a colourless solution.
8. Repeat steps 1 to 7 four more times, with different concentrations. (0.01, 0.005, 0.0025,
!
!
0.00125)
Data:
!
Experiment 1: 0.02M Kl
Volume of I-: 50ml
Volume of Fe2+ : 50ml
!
Time/min
Volume of S2O3/cm3
Concentration of I-
0
-
5
0.00 - 20.6
20.6
0.02
10
20.6 - 36.1
15.5
0.02
15
00.00 - 17.6
17.6
0.02
20
17.6 - 30.4
12.8
0.02
25
30.4 - 44.7
14.3
Concentration l2 0.02
0.02
!
Experiment 2: 0.01M Kl
Volume of I-: 50ml
Volume of Fe2+ : 50ml
!
Time/min
Volume of S2O3/cm3
Concentration of I-
0
-
0.01
5
00.00 - 16.6
16.6
0.01
10
16.6 - 30.8
14.2
0.01
15
30.8 - 43.1
12.3
0.01
20
00.00 - 17.8
17.8
0.01
25
17.8 - 29.4
11.6
0.01
Concentration l2 Experiment 3: 0.005M Kl
Volume of I-: 50ml
P2
!
!
!
!
!
Chemistry Practical 4: Measuring rate of reaction
Aim of experiment:
To determine the rate of reaction when the concentration of I2 increases.
!
!
!
Chemical equation:
2Fe3+ + 2I- --> 2Fe2+ + I2
!
!
!
Apparatus & materials:
Apparatus
Quantity
50ml Pipette
1
10ml Pipette
1
Pipette bulb
1
100ml beaker
2
50ml Burette
1
250ml Conical Flask
6
Timer
1
Distilled water
100ml or more
50ml Measuring Cylinder
1
Bottle of starch
1
S2O32-
100ml or more
Fe3+
50ml or more
I-
50ml or more
!
!
!
Procedure:
! pipette 50ml of 0.02M Kl, 50ml of 0.02M Fe3+ into separate beakers.
1.
2. Prepare S2O32- solution in a burette.
3. Pour I- and Fe3+ solution into a conical flask. Start the timer.
4. For every 5 minutes, pipette 10ml of solution mixture into a flask, and 10ml of distilled water to quench the solution.
5. Add 3 drops of starch to the solution.
6. Then, proceed to titrate with S2O32-.
7. The solution will change from blue-black to a colourless solution.
8. Repeat steps 1 to 7 four more times, with different concentrations. (0.01, 0.005, 0.0025,
!
!
0.00125)
Data:
!
Experiment 1: 0.02M Kl
Volume of I-: 50ml
Volume of Fe2+ : 50ml
!
Time/min
Volume of S2O3/cm3
Concentration of I-
0
-
5
0.00 - 20.6
20.6
0.02
10
20.6 - 36.1
15.5
0.02
15
00.00 - 17.6
17.6
0.02
20
17.6 - 30.4
12.8
0.02
25
30.4 - 44.7
14.3
Concentration l2 0.02
0.02
!
Experiment 2: 0.01M Kl
Volume of I-: 50ml
Volume of Fe2+ : 50ml
!
Time/min
Volume of S2O3/cm3
Concentration of I-
0
-
0.01
5
00.00 - 16.6
16.6
0.01
10
16.6 - 30.8
14.2
0.01
15
30.8 - 43.1
12.3
0.01
20
00.00 - 17.8
17.8
0.01
25
17.8 - 29.4
11.6
0.01
Concentration l2 Experiment 3: 0.005M Kl
Volume of I-: 50ml