The document defines rate of reaction as the change in concentration of a reactant or product per unit time. It then describes an experiment to monitor the rate of production of oxygen from hydrogen peroxide using manganese dioxide as a catalyst. The rate is measured by recording the volume of oxygen evolved over time from the reaction. The document includes graphs of the experimental data and questions about calculating rates from the graphs and how changing experimental conditions would affect the reaction rate.

1. Rate of reaction definition
Rate of reaction is the change in
concentration of any one reactant
or product in unit time

2. Monitoring the rate of production of
oxygen from hydrogen peroxide, using
manganese dioxide as catalyst
2
H2O2
MnO2
2
H2O
+
O2
Monitor the rate by measuring the volume of
oxygen evolved over time

3. Procedure
Record the volume of gas in the syringe every
10 s until there is no increase in the volume of gas

4. Procedure

5. How to start the Reaction and
stopwatch at the same time
Pull the thread
to tilt test tube,
and spill its
contents.
At the same
time start the
stopwatch

6. Graph Volume Oxygen
V
O
L
U
M
E
G
A
S
cm3
v Time
160
140
120
100
80
60
40
20
10
20
30
40
TIME sec
50
60
70
80
90

7. V
O
L
U
M
E
G
A
S
cm3
160
140
120
100
80
60
40
20
10
20
30
40
TIME sec
50
60
70
80
90

8. 120cm3
V
O
L
U
M
E
G
A
S
cm3
160
140
120
100
What volume
of gas was
collected
after 30 s ?
80
60
40
20
10
20
30
40
TIME sec
50
60
70
80
90

9. When maximum
volume of oxygen
V
O
L
U
M
E
G
A
S
cm3
160
obtained
140
120
After what
time was
the reaction
finished ?
100
80
60
40
20
10
20
30
40
TIME sec
50
60
70
80
90

10. When half maximum
volume of oxygen
V
O
L
U
M
E
G
A
S
cm3
obtained
160
140
120
When was
the reaction
half finished
?
100
80
60
40
20
10
20
30
40
TIME sec
50
60
70
80
90

11. V
O
L
U
M
E
G
A
S
cm3
160
Y2=150
140
120
What was the
Rate= Y2-Y1
instanteous
X2-X
rate at 30 s ? 1
100
Y1=95
80
Rate= 1.375 cm3/sec
55
150-95
40
50-10
60
40
20
10
X1=10
20
30
40
50
X2=50
60
TIME
70
80
90

12. V
O
L
U
M
E
G
A
S
cm3
160
140
120
100
How would the
graph change if
the solution as
more
concentrated ?
80
60
40
20
10
20
30
40
50
60
70
TIME sec
80
90

13. V
O
L
U
M
E
G
A
S
cm3
160
140
120
100
How would the
graph change if
the temperature
was higher ?
80
60
40
20
30
TIME