Chemical Fundamentals
Student Experiment: Molar Heat
Rationale
Alcohol can be burned as a source of energy instead of using fossil fuels. Smith and Workman [1] say that alcohol has been used as a fuel for the internal combustion engine since its invention. Reports on the use of alcohol as a motor fuel were published in 1907 and detailed research was conducted in the 1920s and 1930s (OCR, 2013).
Alcohols are organic compounds containing Oxygen, Hydrogen and Carbon. They are a family of
hydrocarbons that contain the –OH group. The alcohols are a homologous series containing the functional
–OH group, which determines the characteristic reactions of a compound.
The general formula of alcohols is CnH2n+1OH, where n is a number. Alcohols are also referred to as
alkanols. The simplest alcohol contains a single Carbon atom and is called Methanol. Its molecular
formula is CH3OH. As we move down the homologous series of alcohols, the number of Carbon atoms
increase. Each alcohol molecule differs by –CH2; a single Carbon atom and two Hydrogen atoms.
The figure below is the structural formula of Methanol (CH3OH) and Ethanol (C2H5OH) respectively:
Methanol Ethanol
(Pictures taken From: http://www.gcsescience.com/Methanol.gif and http://www.gcsescience.com/Ethanol.gif)
This table below shows the molecular formulas of the early members of the alcohol homologous series.
It can be seen as we go down the homologous series of alcohols, carbon atoms are added onto the
hydrocarbon chains. These chains are becoming longer and much more complex. Moreover, as we go
down the group, the alcohols’ boiling points, heat of combustions, and other characteristics show changes
as well.
Combustion is principally the oxidation of carbon compounds by oxygen in air to form CO2 if there is a
sufficient amount of oxygen. The hydrogen in a compound forms H2O. Combustion produces heat as
well as carbon dioxide and water. The enthalpy change of combustion is the enthalpy change that occurs
when 1 mole of a fuel is burned completely in oxygen.
(Taken from:
http://www.coursework.info/AS_and_A_Level/Chemistry/Organic_Chemistry/Find_the_enthalpy_chang
e_of_combustion_o_L61656.html#ixzz0fokacpwD)
The heat of combustion (standard enthalpy change of combustion) is the enthalpy change when one mole
of the compound undergoes complete combustion in excess oxygen under standard conditions. It is given
the symbol ∆H˚comb and standard conditions simply refer to room conditions with a temperature of 298K
and pressure of 1 atm.
As a result, the aim of the experiment is to determine whether there is a relationship between the number
of carbon atoms in an alcohol chain and its respective standard enthalpy change of combustion.
Original Experiment
Measure the mass of the empty spirit lamp using the electronic balance. Record the result in Table 1 below. Measure 30 mL of ethanol and pour it into the spirit lamp. Measure the mass of the spirit lamp containing the ethanol and record the result in Table 1. Measure 100 mL of distilled water (record the result in Table 1) and add it to the calorimeter. Insert the stirrer into the calorimeter and set up the thermometer so that the bulb of the thermometer is in the centre of the volume of water. Use the thermometer to record the initial temperature of the water (Ti). Cover the calorimeter with the lid and place it directly over the spirit lamp (Figure 1). Place safety mats around the spirit lamp to limit heat lost to the environment. Use a match to light the spirit lamp. Once the ethanol is burning, start the stopwatch. Record any change in the temperature of the water. Gently stir the water during the heating. Extinguish the spirit lamp and halt the stopwatch as soon as the temperature has risen 30°C. Record the final temperature of the water (Tf). Record the mass of the spirit lamp containing the remaining the ethanol.
Diagram 1 – The setup used.
Research question
To investigate the relationship between the numbers of carbon atoms in an alcohol chain; methanol,
Ethanol and propanol and their respective standard enthalpy change of complete combustions.
Modifications to the methodology
The original experiment was modified by investigating the addition of two other alcohols so that the research could be answered. This also involved taking 5 tests for each alcohol this was done so that the most accurate results were gained. It is assumed that no heat escapes into surrounding but limit the effect of this assumption we put two heatproof mats either side of the spirit lamp so that as much heat was maintained and focused onto the water. In addition to this, a chimney was made so that the flame its self and heat was funnelled onto the water beaker. Aluminium foil was added to surround the temperature probe so that the plastic did not melt.
Management of risks
Hazard
Risk
Precaution
Comments
Glassware (beaker)
When it gets hot you could burn your hand or you could drop it and break it and cut yourself
Use tongs when removing it from the clamp stand. Don’t do the clamp up tight.
Dispose of glass appropriately if broken and record any injuries
Alcohol
Flammable, harmful.
Methanol is toxic leading to blindness if swallowed
Wear PPE, especially safety glasses and gloves. Wash hands after use. Make sure there is ventilation such as an open window.
Seek medical attention if you get burned or ingest any fuels.
Metal stand
Could fall off the table and break your foot
Make sure the setup is position in the middle of the workbench.
Variables
The dependent variable, which I will be measuring, is the temperature rise.
My independent variable is the alcohol/number of carbon atoms.
My control variables are:
• the temperature rise of the water*
• volume of water to be heated†
• the same distance between the spirit burner and the boiling tube
• the same spirit burner each time. I will rinse it out each time with the new alcohol used
* I cannot control this exactly as the temperature might carry on rising after I’ve put out the flame, but I will make sure
that I record the highest temperature reached. I will also stir the water with the thermometer to make sure I get as
accurate result as I can
† I will measure the volume of water as accurately as I can, but I will be limited by the accuracy of the measuring
cylinder. As the density of water is 1.0 g/cm3
, I will measure the mass of the water each time to make sure I get an
accurate measurement.
Qualitative observations
The flame height and direction varied throughout the several tests. Even though the chimney was designed to focus the flame the height still varied. As the metals and clamps were kept at the same distances between tests the different flame hight could affect how much heat was being absorbed by the water. There is not much that could be done to prevent this. The alcohol was colourless and the flame was odourless. The flame was divided into two sections, one was blue and one was yellow.
Summary Data
Methanol
Experiment
Trial 1
Trial 2
Trial 3
Trial 4
Trial 5
Mass of water, g
100.7
99.6
99.7
98.9
101.1
Start Temperature, OC
25.5
24
23.8
25.8
23.8
End Temperature, OC
80.1
83.2
86.9
87.9
88.2
Temperature Changed, OC
54.6
59.2
63.1
62.1
64.4
Start mass (fuel + burner), g
152.44
139.64
128.37
144.07
133.16
End mass (fuel + burner), g
140.11
123.92
116.24
133.77
120.01
Mass of fuel used, g
12.33
15.72
12.13
10.03
13.15
Table 1 – Methanol summarised data.
Ethanol
Experiment
Trial 1
Trial 2
Trial 3
Trial 4
Trial 5
Mass of water, g
99.3
101.6
99.8
100
102.11
Start Temperature, OC
25.1
25.2
24.3
25
24.1
End Temperature, OC
88.5
85.1
86.9
87.9
88.2
Temperature Changed, OC
63.4
59.9
62.6
62.9
64.1
Start mass (fuel + burner), g
135.96
141.85
134.93
153.29
131.11
End mass (fuel + burner), g
128.67
131.95
124.02
144.57
121.85
Mass of fuel used, g
7.29
9.9
10.91
8.72
9.26
Table 2 – Ethanol summarised data
Propanol
Experiment
Trial 1
Trial 2
Trial 3
Trial 4
Trial 5
Mass of water, g
99.03
100.76
100.12
99.89
98.99
Start Temperature, OC
24.2
23.9
25.3
26.2
24.1
End Temperature, OC
86.3
84.4
86.2
95
85.4
Temperature Changed, OC
62.1
60.5
60.9
68.8
61.3
Start mass (fuel + burner), g
135.57
145.59
106.64
129.68
102.93
End mass (fuel + burner), g
126.52
135.14
95.52
119.79
92.7
Mass of fuel used, g
9.05
10.45
11.12
9.89
10.23
Table 3 – Propanol summarised data
These are outliers and won’t be included in the average. The outliers were determined using the interquartile range method.
Processing data
The summarised data was processed to determine the molar heat of the three alcohols shown in Table 4. The researched molar heat values of the three alcohols were used as the ‘true’ value or theoretical values at laboratory conditions. This value was compared with the experimental molar heat produced to determine the accuracy of the experimental results and, therefore, the validity of the experimental process. The measurement uncertainty was converted to percentage uncertainty and propagated to determine the precision of the experimental results and, therefore, the reliability of the experimental process. A spreadsheet program was used to graph the experimental results to allow patterns to be examined.
Formula to process data
Sample calculation for methanol
Average mass of fuel used =
Trial 1 +Trial 2+ Trial 3 ….Number of trial
Average mass of fuel used =
12.33 + 15.72 + 12.13+ 10.03 + 13.155
= 12.672 g
Average Δ temperature=
Trial 1 +Trial 2+ Trial 3 ….Number of trial
Average Δ temperature =
54.6 + 59.2 + 63.1 + 62.1 + 64.45
= 60.68
Uncertainty = ±
range2
Uncertainty of Δ temperature = ±
64.4 – 54.62
= 60.68 OC ± 4.9
Uncertainty = ±
range2
Uncertainty of mass of fuel used = ±
15.72 – 10.032
= 12.672 g ± 2.845
Percentage uncertainty =
Uncertainty of measurementMeasurementx100%
2.84512.672×100=22.4511%
Percentage uncertainty = 22.4511%
Percentage uncertainty =
Uncertainty of measurementMeasurementx100%
4.960.68×100=8.07514832%
Percentage uncertainty = 8.07514832%
Heat of combustion = mcΔt
Heat of combustion = 100 x 4.168 x 60.68
= 25 400.648 j
= 25.4 kj
Moles of Methanol Burnt =
mass of methanolmolar mass of methanol
Average Mass of Methanol Burnt = 12.672g
Molar Mass of Methanol = CH3OH
= (12.01) + (4 x 1.01) + (16)
= 32.05 g/mol
Moles of Methanol Burnt =
12.67232.05
= 0.39538 mol
Molar Heat of Methanol =
Heat of combustionMoles of Methanol Burnt
Molar Heat of Methanol =
25.40.39538
= 64.241995 kJ/mol
Percentage error =
|accepted value – experimental value|accepted value
x 100%
Percentage error =
726–64726
x 100%
= 91.18%
Formula to process data
Sample calculation for ethanol
Average mass of fuel used =
Trial 1 +Trial 2+ Trial 3 ….Number of trial
Average mass of fuel used =
7.29+9.9+10.91+8.72+9.265
= 9.216 g
Average Δ temperature=
Trial 1 +Trial 2+ Trial 3 ….Number of trial
Average Δ temperature =
63.4+59.9+62.6+62.9+64.15
= 62.58
Uncertainty = ±
range2
Uncertainty of Δ temperature = ±
64.1–59.92
= 62.58OC ± 2.1
Uncertainty = ±
range2
Uncertainty of mass of fuel used = ±
10.91–7.292
= 9.216g ± 1.81
Percentage uncertainty =
Uncertainty of measurementMeasurementx100%
2.162.58×100=3.36%
Percentage uncertainty = 3.36%
Percentage uncertainty =
Uncertainty of measurementMeasurementx100%
1.819.216×100=19.64%
Percentage uncertainty = 19.64%
Heat of combustion = mcΔt
Heat of combustion = 100 x 4.168 x 62.58
= 26196 j
=26.20 kj
Moles of ethanol Burnt =
mass of ethanolmolar mass of ethanol
Average Mass of ethanol Burnt = 9.216g
Molar Mass of ethanol = C2H5OH
= (12.01 x 2) + (6 x 1.01) + (16)
= 46.08 g/mol
Moles of ethanol Burnt =
9.21646.08
= 0.2 mol
Molar Heat of ethanol =
Heat of combustionMoles of Methanol Burnt
Molar Heat of ethanol =
26.200.2
= 131 kJ/mol
Percentage error =
|accepted value – experimental value|accepted value
x 100%
Percentage error =
1360–1311360
x 100%
= 90.37%
Formula to process data
Sample calculation for propanol
Average mass of fuel used =
Trial 1 +Trial 2+ Trial 3 ….Number of trial
Average mass of fuel used =
9.05 + 10.45 + 11.12 + 9.89 + 10.235
= 10.148 g
Average Δ temperature=
Trial 1 +Trial 2+ Trial 3 ….Number of trial
Average Δ temperature =
62.1 + 60.5 + 60.9 + 68.8 + 61.35
= 62.72
Uncertainty = ±
range2
Uncertainty of Δ temperature = ±
68.8 – 60.52
= 62.72 OC ± 4.15
Uncertainty = ±
range2
Uncertainty of mass of fuel used = ±
11 12– 9.052
= 10.148 g ± 1.035
Percentage uncertainty =
Uncertainty of measurementMeasurementx100%
4.1562.72×100=6.62%
Percentage uncertainty = 6.62%
ercentage uncertainty =
Uncertainty of measurementMeasurementx100%
1.03510.148×100=10.1991%
Percentage uncertainty =10.1991%
Heat of combustion = mcΔt
Heat of combustion = 100 x 4.186 x 62.72
= 26254.6 j
= 26.25 kj
Moles of Methanol Burnt =
mass of methanolmolar mass of methanol
Average Mass of Methanol Burnt = 10.148g
Molar Mass of Methanol = C3H7OH
= (12.01 x 3) + (8 x 1.01) + (16)
= 60.11 g/mol
Moles of Methanol Burnt =
10.14860.11
= 0.168824 mol
Molar Heat of Methanol =
Heat of combustionMoles of Methanol Burnt
Molar Heat of Methanol =
26.250.168824
= 155.487 kJ/mol
Percentage error =
|accepted value – experimental value|accepted value
x 100%
Percentage error =
2021–155.4872021
x 100%
=92.257 %
Alcohol
Formula
Number of Carbon Atoms
Molar Heat
Percentage Error
Methanol
CH3OH
1
64.241995 kJ/mol
91.18%
Ethanol
C2H5OH
2
131 kJ/mol
90.37%
Propanol
C3H7OH
3
155.487 kJ/mol
92.257%
Graph 1 – Experimental values graphed against the number of carbon atoms in the organic solution
Graph 2 – Experimental Values and True Values
Trends patterns and relationships
It is interesting that the experimental value of ethanol -while still on the line- appears as lower
than the other experimental values. This is not observed in the values based on BE where the five
energy values are perfectly aligned. Ethanol´s value is clearly lower than that of methanol and
slightly lower than the other higher alcohols.
Therefore there seems to be some structural difference between ethanol and the rest, with a
more marked variation with the first member of the homologous series. I tend to believe that this
may result from the significantly lower inductive effect that the ethyl group has on the C-O bond
when compared with the methyl group. If the inductive effect is lower the bond is less polar,
resulting in an increased covalent character and therefore a stronger bond. As the bond is
stronger more energy is needed to break it, and the enthalpy change would therefore be smaller.
The inductive effect is not changed by adding CH2 in the higher alcohols but still there must be
some, as they are slightly lower than methanol (but perfectly aligned with each other). Still other
possibility is that differences result from experimental errors which references do not report.
Results may suggest that the difference in the bond O-H could be affecting alcohols to a different
degree. More data are needed to clarify why the second CH2 affects the C-O bond in ethanol but
not in the rest providing a satisfactory explanation for this anomaly.
Limitations of evidence reliability and viability
1) Around 90% of the heat from the spirit lamp did not reach the base of the tripod stand itself. This
was the main reason of error. Heat was lost very easily. A lot of heat was lost in this manner and
contributed to a lower than expected temperature change in the water. This was undoubtedly, the
main source of experimental error.
2) Although, the copper calorimeter was properly insulated, heat loss was prevalent. The lid had a
hole to allow the thermometer to be placed inside. This meant heat could be lost in this manner as
well.
3) The mass of water might not have been constant throughout the heating process. Some of the
water might have evaporated off, suggesting a mass loss. This would then give different results.
4) It was observed that during the combustion of alcohols, a yellow flame was obtained at times.
This is the sign of the incomplete combustion of alcohols. As a result, carbon monoxide is formed
instead of carbon dioxide. Therefore, this incomplete combustion results in low standard enthalpy
of combustion values as the reaction is not complete.
5) During calculations, the specific heat capacity of the copper calorimeter was not included. This is
wrong. The copper beaker did absorb some heat from the spirit lamp. This should have been
added onto the heat energy absorbed by the water. Due its absence, a lot of heat was absorbed
through the copper calorimeter itself, and this was not calibrated.
Conclusion
I may finally conclude that my hypothesis has been validated both by experimental values found in
cited resources and those calculated using bond energies. The investigation has evidenced that
there is a positive linear relationship between the ΔH of combustion and the number of C atoms in
a homologous series of simple alcohols. It has also shown that results based on bond energies are
lower than those experimentally obtained underlining the relevance of chemical environments in
the energy needed to break specific bonds even when extremely similar. An unexpected small
anomaly was found in the experimental value of ethanol which is not shown in the trend based on
bond energies, reinforcing the limitations that average values may impose on accurate
descriptions
Suggested improvements and extensions
1) This experiment could have been carried out at a place of constant temperature.
2) The calorimeter could have been insulated more. A thick cotton wool could have been added.
3) Minimize the heat lost by ensuring no gas (vapour) is lost during the heating process, by adding
more cotton for insulation or covering the calorimeter with a thick lid.
4) Black coloured cardboard can also be used for preventing heat loss.
5) Stir the water at all times to distribute heat evenly.
6) Blow out the spirit lamp as soon as possible. A delay here means that there is more loss of
alcohol.
7) Carry out the experiment in the presence of excess oxygen to ensure that no incomplete
combustion takes place.
8) Repeat with a much larger variety of alcohols. (C6H13OH, C7H15OH, C8H17OH, etc).
Some alcohols also have slightly different structures. The alcohols we had to choose from included propan2-ol.
This means that the OH group was at a different position in the alcohol. We should test some of these
different alcohols to see if our finding still stands.
It may also be difficult to transfer our results to the real world. Fuels are not usually pure chemicals but
mixtures (for instance alkane fuels). It is likely that alcohol fuels are mixtures of alcohols and not pure. We do
not know from the new methods of production of alcohol fuels ([5] and [6]) how pure the alcohols for the
fuels will be (and mixtures may be better).
Methanol has the lowest combustion energy, but it also needs the least oxygen to burn (see page 6). It
therefore has the lowest chemically correct air-fuel ratio, so an engine burning methanol would have the
most power [1]. But alcohols with fewer carbon atoms might be a problem on a hot summer’s day or at high
altitudes. From butanol upwards, the alcohols are relatively insoluble in water, and will attract less, making
them better for engines.
Raw Data
Trial 1
Beaker – 57.96 g
Ethanol
Propanol
Methanol
Mass of spirit lamp + alcohol
135.96g
135.57
152.44
Mass of water
99.3g
99.03g
100.7
Initial temp of the water
25.1
24.2
25.5
Water temp 20 sec
25.4
24.7
25.6
Water temp 40 min
27.7
26.6
25.7
Water temp 1 min
31
28.1
27.1
Water temp 1:20 min
34.8
29.4
29.7
Water temp 1:40 min
40.1
30.8
31
Water temp 2 min
47.1
32.5
34.4
Water temp 2:20 min
55.5
35.3
38.4
Water temp 2:40 min
65.6
40
41.5
Water Temp 3 min
76.6
45.8
45.7
Water Temp 3:20 min
88.5
48.8
51.8
Water Temp 3:40 min
56.2
57.8
Water Temp 4 min
63.8
63.5
Water Temp 4:20 min
71.9
69.9
Water Temp 4:40 min
78.8
76.1
Water Temp 5 min
86.2
80.1
Final Temp of water
88.5
86.2
80.1
Mass of spirit lamp + remaining alcohol
128.67
126.52
140.11
Trial 2
Beaker – 57.96 g
Ethanol
Propanol
Methanol
Mass of spirit lamp + alcohol
141.85g
145.59
139.64
Mass of water
101.6g
100.76
99.6
Initial temp of the water
25.2
23.9
24
Water temp 20 sec
25.2
24.1
23.9
Water temp 40 sec
25.4
24.8
24.8
Water temp 1 min
26.7
25.8
25.3
Water temp 1:20 min
27.5
27.3
27
Water temp 1:40 min
28.5
29.6
29
Water temp 2 min
31.8
30.6
30.5
Water temp 2:20 min
36
32.4
32.8
Water temp 2:40 min
40.6
34
36.3
Water Temp 3 min
46.6
36.2
41.4
Water Temp 3:20 min
55.4
38.4
44.1
Water Temp 3:40 min
63.2
40.6
46
Water Temp 4 min
70.6
42.3
49.7
Water Temp 4:20 min
76.1
44.3
54.5
Water Temp 4:40 min
85.1
46.7
58.2
Water Temp 5 min
50.8
63.8
Water Temp 5:20 min
55.4
69
Water Temp 5:40 min
62.5
73.6
Water Temp 6 min
70.1
78
Water Temp 6:20 min
77.8
80.5
Water Temp 6:40 min
84.4
Water Temp 7 min
Final Temp of water
85.1
84.4
83.2
Mass of spirit lamp + remaining alcohol
131.95
135.14
123.92
Data from other groups includes trials 3 to 5.
Methanol
Trial 3
Trial 4
Trial 5
Mass of spirit lamp + methanol
128.37g
144.07g
133.16g
Mass of distilled water
99.7
98.9
101.1
The initial temperature of the distilled water oC
23.8 oC
25.0 oC
23.8 oC
Water temperature 20s
23.8 oC
25.2 oC
24.5 oC
Water temperature 40s
25.6 oC
26.5 oC
25.3 oC
Water temperature 60s
28.5 oC
29.4 oC
27.5 oC
Water temperature 80s
32.4 oC
35.9 oC
30.9 oC
Water temperature 100s
37.8 oC
37.8 oC
36.2 oC
Water temperature 120s
41.7 oC
40.1 oC
42.6 oC
Water temperature 140s
47.6 oC
46.5 oC
50.4 oC
Water temperature 160s
54.0 oC
54.3 oC
57.6 oC
Water temperature 180s
60.2 oC
61.5 oC
63.9 oC
Water temperature 200s
69.2 oC
70.8 oC
70.2 oC
Water temperature 220s
77.2 oC
79.9 oC
80.6 oC
Water temperature 240s
86.9 oC
87.9 oC
88.2 oC
Point where reaction had a temperature increase of 60OC
Between 220-240s at 83.8oC
Between 220-240s at 85.0oC
Between 220-240s at 83.8 oC
Mass of spirit lamp + remaining methanol
116.24g
133.77g
120.01g
Mass of methanol used in the reaction
12.13g
10.3g
13.15g
Ethanol
Trial 3
Trial 4
Trial 5
Mass of spirit lamp + ethanol
134.93g
153.29g
131.11
Mass (volume) of distilled water
99.8
100
102.11
The initial temperature of the distilled water oC
24.3 oC
25.0 oC
25.0 oC
Water temperature 20s
24.8oC
25.5 oC
25.1 oC
Water temperature 40s
26.7 oC
26.8 oC
26.7 oC
Water temperature 60s
29.2 oC
28.6 oC
27.7 oC
Water temperature 80s
31.9 oC
31.1 oC
30.6 oC
Water temperature 100s
34.4 oC
34.4 oC
35.6 oC
Water temperature 120s
39.1 oC
40.5 oC
43.5 oC
Water temperature 140s
43.4 oC
45.8 oC
51.3 oC
Water temperature 160s
54.3 oC
54.8 oC
60.5 oC
Water temperature 180s
58.2 oC
65.8 oC
70.7 oC
Water temperature 200s
65.7 oC
72.6 oC
82.4 oC
Water temperature 220s
77.7 oC
82.2 oC
97.4 oC
Water temperature 240s
87.7 oC
96.4 oC
100 oC
Point where reaction had a temperature increase of 60OC
Between 220-240s at 84.3oC
Between 220-240s at 85.0oC
Between 200-220s at 85.0 oC
Mass of spirit lamp + remaining ethanol
124.02g
144.57g
121.85g
Mass of ethanol used in the reaction
10.91g
8.72g
9.26g
Propanol
Trial 3
Trial 4
Trial 5
Mass of spirit lamp + propanol
106.64g
129.68g
102.93g
Mass (volume) of distilled water
100.12
99.89
98.99
The initial temperature of the distilled water oC
25.3 oC
26.2 oC
24.1 oC
Water temperature 20s
26.1 oC
26.9 oC
25.7 oC
Water temperature 40s
28.2 oC
28.0 oC
30.4 oC
Water temperature 60s
32.1 oC
31.9 oC
35.0 oC
Water temperature 80s
34.4 oC
36.8 oC
37.6 oC
Water temperature 100s
38.7 oC
44.7 oC
41.7 oC
Water temperature 120s
47.8 oC
49.7 oC
47.7 oC
Water temperature 140s
59.7 oC
58.3 oC
62.1 oC
Water temperature 160s
72.4 oC
66.7 oC
71.2 oC
Water temperature 180s
84.3 oC
80.9 oC
83.2 oC
Water temperature 200s
98.7 oC
99.2 oC
99.3 oC
Water temperature 220s
100.2 oC
Over 100 oC and boiling
Over 100 oC and boiling
Water temperature 240s
Over 100 oC and boiling
Over 100 oC and boiling
Over 100 oC and boiling
Point where reaction had a temperature increase of 60OC
Between 180-200s at 85.3 oC
Between 180-200s at 85.0 oC
Between 180-200s at 85.0 oC
Mass of spirit lamp + remaining propanol
97.99g
119.53g
93.18g
Mass of propanol used in the reaction
8.65g
10.15g
9.75g
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