PRINCES TOWN WEST SECONDARY
CAPE UNIT 2
CHEMISTRY LABS
2011 - 2012
Princes Town West Secondary Unit 2 Chemistry Labs
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#
Title
Lab # 1
Organic Compounds : To determine which organic compound is contained in the
bottles labelled A, B, C and D
Organic Compounds: To determine which organic compound is contained in the
bottles labelled P, Q, R and S.
Plan and Design : Organic Chemistry
Organic Chemistry: To investigate the relative acidities of alcohols, phenols and
carboxylic acids
Analytical Chemistry : The degree of uncertainty
Crystallization
Analytical Chemistry : Gravimetric Analysis - percentage oxalate in an unknown
sample
Analytical Chemistry : Gravimetric Analysis - Vitamin C Tablet
Analytical Chemistry : Spectroscopy : UV/Vis
Analytical Chemistry : Quantitative Titration
Chromatography : Paper Chromatography Pigment in leaves
Chromatography : Paper Chromatography Inks
Solvent Extraction
Plan Design: Environmental Chemistry
Simple and Fractional Distillation
Environmental Chemistry : Organic Compounds
Plan Design: To determine the acidity / pH of a soil sample
Analytical Chemistry Back Titration
Environmental test for pollutants in water.
Plan and Design : Analytical Chemistry (Gravimetric)
Lab # 2
Lab # 3
Lab # 4
Lab # 5
Lab # 6
Lab # 7
Lab # 8
Lab# 9
Lab# 10
Lab# 11
Lab# 12
Lab# 13
Lab # 14
Lab # 15
Lab # 16
Lab # 17
Lab # 18
Lab # 19
Lab # 20
Princes Town West Secondary Unit 2 Chemistry Labs
Skills
2|Page
Lab # 1
Skills
Assessed:
Date:
O/R/
R
M/M
A/I
P/D
Title
: Organic Compounds
Aim
: To determine which organic compound is contained in the bottles labelled A,
B, C and D.
Apparatus
and
Material
:
1. Test Tubes
2. Boiling Tubes
3. 250 ml Beaker(Labelled Organic
Waste)
4. Magnesium Powder or Turnings
5. Sodium Carbonate
6. 2,4dinitrophenyihydrazine
7. Aqueous Silver Nitrate
8. Aqueous Sodium
Hydroxide
9. Aqueous Ammonia
10. Acidified Potassium
Dichromate
Aqueous solutions, A, B, C and D. Each solution contains one of the
following.
I. an alcohol
II. an aldehyde
III. a carboxylic acid
IV. a ketone
Procedure
:
1. You are to perform the tests below and from the results establish
which type of organic compound is contained in each of A, B, C and
D.
2. After each test discard the contents of the tubes into the 250 cm3
beaker, labelled organic waste. Rinse and re-use the tubes for the
remaining tests.
3. Tests for gases are at the end of this lab sheet.
Princes Town West Secondary Unit 2 Chemistry Labs
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Test (a)
Place 1 cm depth of each of the solutions A, B, C and D into separate test-tubes.
To each tube add a small quantity of magnesium powder or turnings.
Identify any gas given off and record the test you used to make the identification.
Test (b)
Place 1 cm depth of each of the solutions A, B, C and D into separate test-tubes.
To each tube add a small quantity of powdered sodium carbonate.
Identify any gas given off and record the test you used to make the identification.
Test (c)
Place 1 cm depth of each of the solutions A, B, C and D into separate test-tubes.
To each tube add 1 cm depth of 2,4-dinitrophenylhydrazine reagent.
:
Place 1 cm depth of each of the solutions A, B, C and D into separate test-tubes.
Place 2 cm depth of aqueous silver nitrate in a boiling-tube and add to it 1 cm
depth of aqueous sodium hydroxide. This will produce a precipitate of silver
oxide.
Test (d)
Test (e)
Observati
ons and
Results
:
Use a dropping pipette to add dilute aqueous ammonia to this mixture until the
precipitate of silver oxide just dissolves.
Do not add an excess of aqueous ammonia.
To each of the tubes containing A, B, C and D add 1 cm depth of the silvercontaining solution you have just prepared.
Place 1 cm depth of each of the solutions A, B, C and D into separate boiling-tubes.
To each tube add a few drops of acidified potassium dichromate(V1) to give a
yellow-orange solution. Warm the tube gently.
Aqueous
Solutions
B
C
(Alcohol)
(Ketone
)
(Alde
hyde)
Test (a)
No Rxn
No Rxn
No
Rxn
Test (b)
No Rxn
No Rxn
No
Rxn
Test (c)
No Visible
Rxn
Yellow
brown/
(orange)
ppt
formed
A
No ppt
formed
∴
Princes Town West Secondary Unit 2 Chemistry Labs
Yello
w
brown
/
(orang
e) ppt
D
(Carboxylic Acid)
Pop with glowing splint ∴ H2 gas
given off. Hence Compound D is
the acid.
effervescence and gas bubbled
through Ca(OH)2 White ppt
formed.
Gas given off CO2. D is the
carboxylic Acid.
No Visible Rxn
No ppt formed
4|Page
Aldehyd
e or
Ketone
No Visible
Rxn
Test (d)
No ppt
formed
Test (e)
Discussion
:
•
Green
solution
formed
indicating
Cr3+ ions
hence an
alcohol or
aldehyde
No
Visible
Rxn
No ppt
formed
No
Visible
Rxn
forme
d∴
Aldeh
yde or
Keton
e
Silver
ppt
forme
d on
ring
of test
tube ∴
silver
mirror
effect
hence
comp
ound
C is
the
Aldeh
yde
Green
soluti
on
forme
d
indica
ting
Cr3+
ions
hence
an
alcoh
ol or
aldeh
yde
No Visible Rxn
No ppt formed
No Visible Rxn
Test (a)
Compound D is the acid as H2 gas was given off and identified
○
Princes Town West Secondary Unit 2 Chemistry Labs
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○
•
Test (b)
Effervescence CO2 given off as confirmation with white ppt
○
forming in CaA(OH)2
2R-COOH(aq)+Na2CO3(s)yields 2R-COO-Na+(aq)+
○
CO2g+H2O(l)
CO2g+Ca(OH)2 yields CaCO3(s)+H2O(l)
○
○
•
∴ Substance D is the acid as no other reactions
were observed by the other substances.
Test (c)
Yellow brown (or orange) ppt seen for B and C indication it’s a
○
carbonyl compound.
○
○
○
•
by the pop with the glowing splint.
2R-COOH(aq)+2Mg(s)yields 2R-COO-Mg+(aq)+ H2(g)
∴ Substance B and C are either a ketone or
aldehyde
RCHO+ C6H3NO22.NHNH2yields RCH=NNC6H3NO22
s+H2Ol
RR'CO+ C6H3NO22.NHNH2yields R'RC=NNC6H3NO22
s+H2Ol
Test (d)
2Ag(NH3)2 (aq)++ RCHO(l)+3OH(aq)- yields 2Ag(s)+
○
RCOO(aq)-+ 4NH3 g+ 2H2Ol
Tollen’s reagent only reacts with aldehydes to give the silver
○
mirror effect ∴ substance C is the aldehyde.
•
Test (e)
Substance A is an Alcohol because it reduces aqueous K2Cr2O7
○
to a green Cr3+ but did not react with either Tollen’s reagent or
2,4,-dinitrophenylhydrazine reagents.
Substance B ∴ has to be the ketone by reason of
○
elimination and its reaction with 2,4 ,dinitrophenylhydrazine.
Conclusio
n
:
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gas
test and test result
ammonia, NH3
turns damp red litmus paper blue
carbon dioxide, CO 2
gives a white ppt. with limewater
(ppt. dissolves with excess CO 2)
chlorine, 012
bleaches damp litmus paper
hydrogen, H2
'pops' with a lighted splint
oxygen, 02
sulphur dioxide, 80 2
relights a glowing splint
turns potassium dichromate(VI) (aq) from orange to
green
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Lab # 2
Skills
Assessed:
Date:
O/R/
R
M/M
A/I

P/D
Title
: Organic Compounds
Aim
: To determine which organic compound is contained in the bottles labelled P,
Q, R and S.
Apparatus
and
Material
:
1. Test Tubes
2. Boiling Tubes
3. 250 ml Beaker(Labelled Organic
Waste)
4. Magnesium Powder or Turnings
5. Sodium Carbonate
6. 2,4dinitrophenyihydrazine
7. Aqueous Silver Nitrate
8. Aqueous Sodium
Hydroxide
9. Aqueous Ammonia
10. Acidified Potassium
Dichromate
You are provided with four organic substances P, Q, R and S.
Each belongs to one of the following classes of compounds:
I. An aromatic alcohol
II. An alkene
III. An alkane
IV. An alkyl halide
Procedure
:
1. You are to perform the tests below and from the results establish
which type of organic compound is contained in each of P, Q, R and
S.
2. After each test discard the contents of the tubes into the 250 cm3
beaker, labelled organic waste. Rinse and re-use the tubes for the
remaining tests.
3. Gloves, eye protection and lab coats must be worn. The Fume hood
must be used where specified.
Princes Town West Secondary Unit 2 Chemistry Labs
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Place 5 drops of each of the substances P, Q, R and S into separate
Test (a)
Test (b)
test-tubes. Cover each test-tube completely with foil. In the fume
cu board add 5 dro s of bromine to each. Sto er for 5-10 minutes
Place 5 drops of each of the substances P, Q, R and S into separate
test-tubes. In the fume cupboard add 5 drops of bromine to each.
Place 5 drops of each of the substances P, Q, R and S into separate
Test (c)
test-tubes. Add 2% aqueous potassium manganate(VII) drop wise.
:
Place 2 drops of each of the substances P, Q, R and S into separate
Test (d) test-tubes. To each tube add 1 cm depth of aqueous Iron(III) chlorid
solution. Warm if necessary.
Test (e)
Observatio
ns and
Results
Place 2 drops of each of the substances P, Q, R and S into separate
test-tubes. To each tube add 1 cm depth of aqueous silver nitrate
Aqueous
Solutions
P
Q
R
S
Test (a)
Test (b)
:
Test (c)
Test (d)
Test (e)
Discussion
:
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Conclusion :
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Lab # 3
Skills
Assessed:
Date:
O/R/
R
M/M
A/I
P/D
Title
: Plan and Design : Organic Chemistry
Aim
:
Case

You are provided with solutions VF 3, VF 4 and VF 5.
The solutions are:
1.0 mol dm–3 Propanone
1.0 mol dm–3 Propanal
0.5 mol dm–3 Propanoic Acid
You are to plan experiments that will enable you to identify the
solution that matches each of
: VF 3, VF 4 and VF 5.
You have available the following apparatus:
–10 °C to 110 °C thermometer,
100 cm3 beaker, measuring cylinder, and the following reagents
LiAlH4, EDTA, Fehlings Reagent, 2,4 DNPH, and one of your choice.
(a) You are to identify, by the minimum number of practical
steps, which of the solutions contains Propanone
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1.
Apparatus
and
Material
:
Procedure
:
2.
1.
2.
3.
4.
5.
6.
Observatio
ns and
Results
:
Data
Analysis and
:
Interpretati
on
Discussion
:
•
•
Conclusion
:
Lab # 4
Date:
Skills
Assessed:
O/R/
R
M/M
A/I
Princes Town West Secondary Unit 2 Chemistry Labs

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P/D
Title
: Organic Chemistry
Aim
: To investigate the relative acidities of alcohols, phenols and carboxylic acids
The relative acidities of alcohols, phenols and carboxylic acids depends on
the ease at which the molecule gives up a proton to water in an aqueous
solution. Strong acids are those which easily donate a proton and hence is
fully ionised in an aqueous solution.
Example:
HCl H+ + Cl-
Theory
Alcohols do not give up H+ ions readily due to the presence of the OH
group, because the alkyl group donates electrons to the O atom, thereby
decreasing the tendency for the H atom to ionise.
ROH + H2O
RO- + H3O+
Phenols tend to give up H+ more readily than alcohols because electrons
: from the OH bond tends to be localized around the benzene ring, and thus
increases the tendency for the H atom to ionise.
Carboxylic acids are the strongest acid of all the three, and tends to give up
H+ more readily than alcohol and phenols. The carboxyl group
tends
to pull electrons away from the OH bond, hence weakening the OH bond
and making it easier for the H atom to ionise.
RCOOH +
Apparatus
and
Material
:
H2O
RCOO- + H3O+
1. Samples of Ethanol, Phenol and
Ethanoic acid.
2. Magnesium Ribbon
3. Solid Na2CO3
Princes Town West Secondary Unit 2 Chemistry Labs
5. Apparatus to test gas,
splint, litmus, Ca(OH)2(aq)
6. pH meter / pH paper
7. spatula
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4. Test tubes
Procedure
:
8. Glass rod
1. A piece of Magnesium Ribbon was added to 4 cm3 of ethanol in a
test tube and observations were recorded
2. Solid Na2CO3 was added to 4 cm3 of ethanol in a test tube and
observations were recorded
3. The pH meter was then used to find the pH of ethanol, and this value
was also recorded.
4. The above procedure was then repeated using phenol and ethanoic
acid.
Table 1:
Observation
s and
Results
Observation table
Ethanol
:
Phenol
Ethanoic Acid
Magnesium Ribbon
Solid Na2CO3
pH
Data
Analysis
and
Interpretati
on
1. Which samples reacted with Mg? Write a balanced equation for any
reaction which occurred.
:
2. Which samples reaction with Solid Na2CO3? Write a balanced equation for
any reaction that occurred.
3. Use the results of the experiment to deduce the order of increasing
acidities of the samples.
Discussion
:
Conclusion
:
•
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Lab # 5
Skills
Assessed:
Date:
O/R/
R
M/M

A/I
P/D
Title
: Analytical Chemistry : The degree of uncertainty
Aim
: To determine the degree of uncertainty between a measuring cylinder and a
burette.
Apparatus
and
Material
:
1. 50 cm3 burette (Class A)
2. 10 cm3 measuring cylinder (Class A)
3. Distilled water
Procedure
:
1. The burette was filled to a known volume and record the volume
2. 25 drops of water was delivered drop wise into a measuring cylinder
and record both the measuring cylinder and new burette reading
3. This process was repeated in steps of 25 drops until 200 drops were
delivered.
4. The results were tabulated.
5. A graph was drawn vol of burette against vol in cylinder
6. A best fit line was drawn
7. Calculate the Standard Deviation between volumes in the burette and
the measuring cylinder.
Observatio
ns and
Results
:
Table: 1
Readings obtained from the burette and measuring cylinder respectively.
No. of Drops
25
50
75
100
125
150
200
Final Burette Reading / cm 3
Initial Burette Reading / cm 3
Total Vol of drops Burette / cm3
Vol in measuring cylinder / cm 3
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S.D. between Readings
Draw a graph of volume of burette versus volume of measuring cylinder
Graph
Data
Analysis
:
1. From the graph determine when 4 cm3 of the burette is delivered the
volume of measuring cylinder?
2. From the graph when 8.2 cm3 of water is delivered from the burette
the reading in the measuring cylinder ?
3. Which instrument is considered to be accurate
4. Which instrument is considered to be precise
5. Explain your answer for questions 3 and 4.
Discussion
:
•
•
•
•
Conclusion
:
Lab # NA
Date:
Skills
Assessed:
O/R/R
M/M

A/I
P/D
Princes Town West Secondary Unit 2 Chemistry Labs
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Title
: Analytical Chemistry : Measurements
Aim
: Uncertainty of measurements of volumes and masses
Apparatu
s and
Material
:
Procedur
e
:
Part A
1. Burette, 50 mL, Class B
2. Graduated pipette, 10 mL, Class B
3. Volumetric flasks, 25 mL, Class A
and B
4. Measuring cylinder, 10 mL
5. 15 Vials and stoppers
6. Tissue
7. Top loading balance
8. Analytical balance
9. Unknown liquid, 200 mL.
(0.789 g ml-1)
10. Distilled water
11. Pipette filler
1. All glassware was rinsed with distilled water, and then 2 mL of
unknown liquid provided.
2. The empty vials and the volumetric flasks were labelled
3. The mass of the empty dried sample vials with their stoppers in place
were weighed. Precaution was taken no to interchange stoppers among
vials.
4. The burette, graduated pipette, and measuring cylinder were used to
transfer 10 mL of the unknown liquid into different vials.
5. The vials were stoppered and their loaded weights were recorded.
6. This was repeated until a total of three (3) loaded sample vials for each
piece of measuring equipment.
7. Results were recorded in Table 1.
Part B
1. Each volumetric flask was filled to the 25 mL mark with the unknown
liquid ensuring that no liquid is spilled on the outside.
2. The volumetric flasks were stoppered and there loaded weights were
recorded.
3. The unknown liquid in the flasks were completely transferred into a
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sample vial, again ensuring that no liquid is spilled on the outside.
4. The empty volumetric flasks with their stoppers were reweighed.
5. Results were recorder in Table 1.
1. Using a top loading balance combined masses of 2, 4, 6, 8, and 10, 100
g weights were obtained.
Part C
2. A graph was plotted of mass versus number of weights to obtain a best
fit line through the points.
1. The weight of two 100 g weights were measured using a top loading
balance first by:
a. The individual masses and
b. The combined masses of two
2. This procedure was then repeated on an analytical balance.
Part D
Observatio
ns and
Results
:
Part A and B: Table 1: Uncertainty of Measurements of Volumetric Apparatus
Apparatus
Burette
1
2
3
Loaded
19.11
75
19.0
251
18.
92
38
Empty
11.08
93
11.0
073
10.
89
85
Mass
8.028
2
8.01
78
8.0
25
3
Loaded
18.88
71
18.9
043
19.
06
29
Empty
10.89
47
10.8
963
11.
02
64
Mass
7.992
4
8.00
8
8.0
36
Class B ± 0.06
Graduated Pipette
Class B ± 0.06
Princes Town West Secondary Unit 2 Chemistry Labs
Average
8.0238
8.0123
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5
Measuring Cylinder
Loaded
18.79
94
18.7
795
18.
92
84
Empty
11.07
05
11.0
494
11.
21
51
Mass
7.728
9
7.73
01
7.7
13
3
Loaded
21.92
82
21.9
17
21.
91
5
Empty
14.02
95
14.0
325
14.
02
96
Mass
7.898
7
7.88
45
7.8
85
4
Loaded
23.66
78
23.6
576
23.
64
85
Empty
15.73
82
15.7
443
15.
75
62
Mass
7.929
6
7.91
33
7.8
92
3
Class B ± 0.1 @ 20°C
Volumetric Flask A
Class B ± 0.02 @ 20°C
Volumetric Flask B
Class B ± 0.04 @ 20°C
7.7241
7.8895
7.9117
Part C
i.
100 g Weights
Slope
Mass (g)
2
200.04
4
400.07
6
600.1
8
800.14
10
1000.17
100.01625
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ii.
Mass (g) 10100 g Weights
Group 1
Mass( g) Average
200.
040
400
.07
60
0.1
0
80
0.
14
10
00
.1
7
100.016
Group 2
200.
065
400
.17
60
0.2
4
80
0.
14
10
00
.3
6
100.037
Group 3
200.
03
400
.17
60
0.1
2
80
0.
11
10
00
.2
100.021
Group 4
200.
06
400
.12
60
0.1
7
80
0.
22
10
00
.0
7
100.001
Avera
ge
Masse
s
100.019
Part D
iii. Mass 1-100 g
Weight
Top Loading Balance
Analytical Balance
A
100.02
100.003
B
100.02
100.001
100.02
100.002
200.04
200.004
Average Mass
Mass Both 100 g
Weights
Princes Town West Secondary Unit 2 Chemistry Labs
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Part C
Graph
Standard Deviation and Gossett T-Function of Part A and B
Data
Analysis
Standard Deviation =
S
.
D
.
1
Apparatus
Loaded
:
Empty
Mass
Loaded
Empty
Graduated
Pipette
Mass
(xx)2
Measuring
Cylinder
Loaded
Empty
3
19.117
5
11.089
3
19.02
51
11.00
73
18.923
8
10.898
5
8.0282
8.017
8
8.0253
Burette
(xx)2
2
0.0000
197
0.000
0356
0.0000
02351
18.887
1
10.894
7
18.90
43
10.89
63
19.062
9
11.026
4
7.9924
8.008
8.0365
0.0003
96
0.000
018
0.0005
86
18.799
4
11.070
5
18.77
95
11.04
94
18.928
4
11.215
1
Princes Town West Secondary Unit 2 Chemistry Labs
Av
era
ge
(x
x)
2
(
x
x
)
2
2
Gossett’s T-Function
t= 4.302
λ=sd×t(p,n-1)n
8.0
23
8
5.
76
1E
05
0
.
0
0
5
4
0.0133
1.0
00
E03
0.
0
2
2
4
0.0556
8.0
12
3
26 | P a g e
Mass
(xx)2
Loaded
Empty
Volumetric
Flask A
Mass
(xx)2
Loaded
Volumetric
Flask B
Empty
Mass
(xx)2
7.7289
7.730
1
0.0000
23
0.000
036
21.928
2
14.029
5
21.91
7
14.03
25
7.8987
7.884
5
7.7133
0.0001
17
0
.
0
0
9
4
0.0233
1.
26
4E
04
0
.
0
0
8
0
0.0198
6.
99
3E
04
0
.
0
1
8
7
0.0465
14.029
6
7.8854
0.000
025
0.0000
17
23.667
8
15.738
2
23.65
76
15.74
43
23.648
5
15.756
2
7.9296
7.913
3
7.8923
0.000
002
1.
75
7E
04
21.915
0.0000
84
0.0003
19
7.7
24
1
7.8
89
5
7.9
11
7
0.0003
78
Part C
True Value Accurate Measure
Discussio
n
Part A
:
•
The analysis showed that the burette showed reliable results when
compared to the other volumetric instruments having the lowest
deviation from the means and an acceptable confidence level of <0.05.
•
The pipette in this experiment was the least accurate, having highest
deviation when comparing means and an unacceptable confidence
level. This result defies convention of the accuracy of the pipette and
therefore the results suggest human error may have resulted in this
disparity.
•
The measuring cylinder provided a reasonable accurate measure of
Princes Town West Secondary Unit 2 Chemistry Labs
27 | P a g e
volume in the Laboratory.
Part B
•
Comparing the accuracy of various Classes of volumetric apparatus it
was clearly seen that Class A apparatus showed a high degree of
accuracy when compared to Class B apparatus, which is expected by
convention. The confidence level for the Class A was less than that of
the Class B indicating the reliability in the results.
Part C
•
The accuracy of Group experiment showed that Group 1 was the
closest to the accurate value whilst the rest of the group even though
were precise were not accurate.
Part D
•
When comparing the analytical balance to the top loading balance it
was found the analytical balance was more accurate in its measure of
weights as expected by convention.
Conclusio
n
:
The experiment was conducted successfully. An understanding of
measurements accuracy and precision was clearly exemplified.
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Lab # 6
Skills
Assessed:
Date:
O/R/
R
M/M

A/I
P/D
Title
: Crystallization
Aim
: To determine the number of moles of water of crystallization in hydrated
MgSO4.xH2O
Theory
Hydrated salts contain water of crystallization which can be removed by
: heating. The hydrated salt is heated and weighed repeatedly until a constant
mass is obtained. This loss in mass of the salt can then be used to calculate
the number of moles of water of crystallization.
Apparatus
and
Material
Procedure
:
:
1. Hydrated Magnesium sulphate
MgSO4.xH2O
2. Hard glass test tube and holder
3. Balance
4. Bunsen burner
1. The empty hard glass test tube was weighed and this value was
recorded.
2. 6 g of hydrated magnesium sulphate was then placed in the test tube
and reweighed. Readings were recorded.
3. The test tube was then heated gently initially and then more strongly
to remove any water that was present. Heating was stopped if the salt
started to decompose or emit white fumes.
4. The test tube was allowed to cool and then the tube and its contents
were reweighed and this value was recorded
5. The heating, cooling and weighing process was repeated until a
constant mass was obtained. All the readings were recorded.
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Table 1
Mass of hydrated magnesium sulphate
Mass of test tube and hydrated magnesium
sulphate / g
Mass of empty test tube /g
Mass of hydrated magnesium sulphate /g
Table 2
Observation
s and
Results
Mass of hydrated magnesium sulphate after
heating
Mass of test tube and hydrated magnesium
:
sulphate after heating / g
Mass of empty test tube /g
Mass of hydrated magnesium sulphate
after heating /g
Data
Analysis
and
Interpretati
on
:
1. Number of moles of anhydrous MgSO4 in the sample
2. Determine the mass of water driven out of the sample
3. Number of moles of water driven out from the sample
4. Number of moles of water of crystallization in one mole of hydrated
MgSO4
= number of moles of water driven out from the samplenumber of
moles of anhydrous magnesium sulphate in the sample
5. Write an equation for the formation of anhydrous MgSO4 from
hydrated magnesium sulphate.
Discussion
:
•
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30 | P a g e
Conclusion
:
Princes Town West Secondary Unit 2 Chemistry Labs
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Lab # 7
Skills
Assessed:
Date:
O/R/
R
M/M

A/I
P/D
Title
: Analytical Chemistry : Gravimetric Analysis
Aim
: Standardisation of a permanganate solution and determination of the
percentage oxalate in an unknown sample
Apparatus
and
Material
:
Procedure
:
1. 4 – 250 mL conical flask
2. Burette and funnel
3. Retort stand and clamp
4. 1 white tile
5. 2 sample vials with stoppers
6. Bunsen burner/ tripod / wire gauze
7. Thermometer
8. 25 mL measuring cylinder
9. 10 mL measuring cylinder
10. 25 mL Pipette and pipette filler
11. 2 spatulas
12. Analytical balance
13. K2C2O4.H2O salt
14. 3.0 M H2SO4
15. ≈0.02 M KMnO4 solution
16. Distilled water
17. Unknown oxalate sample
18. 250 mL volumetric flask
19. Laboratory cloth
1. ~1.5 grams of K2C2O4.H2O salt (Potassium oxalate) was accurately
weighed and dissolved properly into a 250 ml volumetric flask and
then made up to the mark.
2. 25 ml of K2C2O4 standard was pipette into a conical flask and 15 mL
of 3.0 M H2SO4 was added.
3. The mixture was heated to about 85°C with a Bunsen burner and
ensuring it did not came to a boil temperature. The temperature was
monitored with a clean thermometer.
4. Using a laboratory cloth to hold the flask the solution was titrated
against permanganate with constant swirling until the pink colour of
the permanganate begins to take a few seconds to fade.
5. The temperature was ensured to be about 70 °C before continuing to
titrate drop-wise to reach the end point which was a pale pink
Princes Town West Secondary Unit 2 Chemistry Labs
32 | P a g e
colouration that persists.
6. The titration was repeated twice more to ensure reliability of the titre
value.
7. The mass of the unknown was accurately weighed and dissolved in
50 mL of distilled water in a 250 mL Volumetric flask and then made
up to the mark
8. 15 mL of 3M H2SO4 was added to the unknown oxalate solution and
titrated with the standardised KMnO4 as outlined in procedure # 2 to
6.
9. The mass of the unknown was repeatedly weighed until the mass
produced a titre value close to standardisation value of the
permanganate.
Mass of K2C2O4.H2O salt used: ________ g
Table: 1
Standardisation of KMnO4.
Roug
h
:
1
2
3
Averag
e
Final Burette Reading / cm 3
Initial Burette Reading / cm 3
Observatio
ns and
Results
Total Vol of Burette / cm3
Table: 2
Determination of the unknown concentration of oxalate.
Roug
h
1
2
3
Mass of unknown used /g
Final Burette Reading / cm 3
Initial Burette Reading / cm 3
Total Vol of Burette / cm3
Data
Analysis
:
1. Calculation of the Molarity of the permanganate solution
2. Calculation of the percentage oxalate in the unknown mixture :
3. Why the unknown was repeatedly weighed to produce a titre value
close to that of the permanganate.
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33 | P a g e
Discussion
:
•
•
•
Conclusion
:
•
•
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34 | P a g e
Lab # 8
Skills
Assessed:
Date:
O/R/
R
M/M

A/I
P/D
Title
: Analytical Chemistry : Gravimetric Analysis
Aim
: To determine the Ascorbic Acid concentration in a commercially available
Vitamin C Tablet.
Theory
VITAMIN C ANALYSIS
Step 1: Potassium iodate reacts with iodide to form the complex trihalide
I3- : IO3-+ 8I-+ 6H+yields 3I3- + 3H2O
Anion
Step 2: The trihalide ion reacts with vitamin C :
: C6H8O6+ I3-yieldsC6H6O6 + 2H++ 3I-
Step 3: Remaining trihalide is determined with thiosulfate
I3-+ 2S2O32- yields 3I- + S4O62-
Apparatus
and
Material
:
1.
3.
2. 1 Wash bottle with distilled water
2 White tiles
2 100 mL and 2 250 mL
4.
2 Spatulas
Beakers
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5.
7.
9.
11.
13.
15.
17.
19.
21.
23.
2 sample vials with stoppers
6.
3 25 mL Pipettes and 3 pipette
fillers
8. 2 25 mL, & 2 — 10 mL Measuring
cylinders
1 250 mL, Volumetric flask
6 - 250 mL conical flasks
2 — 50 mL Burettes and
2 funnels
Cotton wool, tissue &
lab cloth
3 Filter funnels
1 Mortar and pestle
2 Pasteur pipettes
2 Retort stands and
10.
12.
14.
16.
18.
20.
22.
Analytical & top loading
balances
1000 mg vitamin C tablet in
vial
KIO3 solution (2.1526 g L -1)
M H2SO4
Sodium thiosulfate solution
10% KI solution
Starch
clamps
24. 1 Wash bottle with distilled water
1 Glass rod
Procedure
: PROCEDURE A: Standardization of Sodium Thiosulfate Solution Using Iodate
Pipette 25 mL of the standard potassium iodate solution provided into a 250 mL
Princes Town West Secondary Unit 2 Chemistry Labs
36 | P a g e
conical flask. Add 15 mL of 1 M sulfuric acid to the flask followed by 10 mL of
10% potassium iodide solution. Titrate the liberated iodine against the sodium
thiosulfate solution until the solution changes to a pale yellow. Then add 10 drops of
starch solution and continue the titration until the blue colouration just disappears.
PROCEDURE B: Determination of Ascorbic Acid content of Vitamin C Tablet
Accurately weigh and record the mass of one Vitamin C tablet. Using a mortar and
pestle pulverize the entire tablet. Transfer 500 mg of the powder (accurately
weighed) to a 100 mL beaker and add 75 mL of 1M H 2SO4. Agitate the mixture with
a glass rod and gravity filter into a 250 mL volumetric flask. To filter the solution
plug the stem of a funnel with a piece of cotton wool. Rinse the cotton with a small
volume of 1M H 2SO4 ensuring that the flow rate is moderate before beginning to
filter the Vitamin C — H2SO4 mixture. Ensure that no solid material goes into the
volumetric flask. If this happens you will need to re-filter. Make the solution up to
250 mL with 1M H 2SO4. Pipette 25 mL of the vitamin C solution into a conical flask
and add 25 mL of standard KIO 3 solution by pipette. Add 10 mL of 10% KI solution
to the mixture and titrate against the standardized thiosulfate solution until the
solution becomes a very pale yellow. Add 10 drops of starch solution and continue
the titration until the blue colouration just disappears. Repeat the experiment until a
satisfactory average is obtained for the end point.
Observatio
ns and
Results
: Using a Suitable Tables Record Your Results.
Data
Analysis
Discussion
Use your average titre volume to calculate
1.
The number of moles of 10; initially added to the solution
:2.
The number of moles of I; produced initially
3.
The number of moles of I; which reacted with thiosulfate
4.
The number of moles of I; which reacted with L-ascorbic acid
:
•
•
•
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37 | P a g e
Conclusion
:
•
•
•
Princes Town West Secondary Unit 2 Chemistry Labs
38 | P a g e
Lab# 9
Skills
Assessed:
Date:
O/R/
R
M/M

A/I

P/D
Title
: Analytical Chemistry : Spectroscopy : UV/Vis
Aim
: To determine the nitrate concentration in an unknown water sample using
UV/vis spectroscopy and the use of Beer Lamberts Law.
Apparatus
and
Material
5. 50 cm3 burette
6. Cadmium reduction
mixture
7. Test tubes
8. Stopwatch
:
1. Evolution 600 UV-Vis
Spectrophotometer)
2. 10 ppm KNO3solution (100 mg
dm3 anhydrous KNO3)
3. 5 – 50 cm3 volumetric flask
4. Unknown water sample
:
1. Using a burette serial dilutions were made of the KNO3 Standard by
transferring 10, 20, 30, 40, and 50 cm3 of KNO3 into their respective
volumetric flask.
Procedure
2. Each flask was then made up to the mark using distilled water and
labelled 2, 4, 6, 8, and 10 ppm respectively.
3. 5 cm3 of each standard was placed into a test tube and labelled,
together with the blank which was distilled water and labelled (0
ppm) and the unknown sample.
4. A spatula of cadmium reduction mixture was added to each test tube
and timed for 12 minutes for each reduction.
5. After the reduction the samples were then measured for Absorbance
on the UV/Vis spectrophotometer at λ= 530 nm.
6. The results were tabulated and a standard curve was drawn.
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39 | P a g e
Table: 1
Observatio
ns and
Results
:
NO3- /
ppm
0
2
4
6
8
10
Unknow
n
Absorbanc
e
0
0.053
0.1157
0.216
7
0.230
9
0.2622
0.1696
1. Plot a graph of Absorbance versus concentration of NO3-
Graph
Data
Analysis
Absorbance values of nitrate ions standards and unknown
:
2. From the graph infer the unknown concentration of the unknown
sample
3. Using Beer-Lamberts Law A=εcl determine the concentration of the
unknown sample
4. When the c = 12 ppm A= ? l = 0.5 cm determine the Absorbance
Discussion
:
•
•
•
•
Conclusion
:
•
Princes Town West Secondary Unit 2 Chemistry Labs
40 | P a g e
Lab# 10
Skills
Assessed:
Date:
O/R/
R
M/M

A/I
P/D
Title
: Analytical Chemistry : Quantitative Titration
Aim
To determine
the concentration of iron(II) ions in an unknown solution and, by a
•
graphical method,
:
•
the volume of an aqueous solution of substance X that will oxidize
the iron(II) ions in 25 cm3 of the unknown.
1. A is 0.02 mol dm-3 potassium
manganate(VII), KMnO4
2. B is the unknown containing iron(II)
ions, Fe2+,
3. C is an aqueous solution of a
substance X.
4. Under acid conditions X oxidizes
iron(II) to iron(III).
Apparatus
and
Material
:
Procedure
: Experiment 1
1. Fill a burette with A, 0.02 mol dm-3 potassium manganate(VII), KMnO4.
2. Pipette 25.0 cm3 of B into a conical flask and add, using the measuring
cylinder provided 10 cm3 of 1 mol dm-3 sulphuric acid.
3. Run A from the burette into the conical flask until the first permanent
pale pink colour remains. This is the end point of the titration.
4. Record your burette readings in Table 1.
5. Repeat the titrations as many times as you think necessary to obtain
accurate results.
6. Make certain that the recorded results show the precision of your
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41 | P a g e
practical work.
Experiment 2
1. Fill the second burette with C, the aqueous solution of X.
2. Pipette 25.0 cm3 of B into a conical flask and add, using the measuring
cylinder provided, 10 cm3 of 1 mol dm-3 sulphuric acid.
3. Add, from the second burette, 4.00 cm 3 of X. This oxidizes some of
the Fe2+ that has been pipetted into the flask.
4. Titrate the remaining Fe2+ in the conical flask with A, potassium
manganate(VII) until the first permanent pale pink colour remains.
5. Record the volume of X added and your burette readings in table 2.
6. One accurate titration will be sufficient. Remember that the volume
added will be less than in Experiment 1 as some of the Fe 2+ has been
oxidized by X.
7. Empty and rinse the conical flask.
8. Repeat Experiment 2, using the volumes of X shown in Table 2.
9. Record your results in Table 2.
Table 1: Titration of A, 0.02 mol dm-3 potassium manganate(VII),
KMnO4 with B, the unknown.
Final burette reading/
cm3
Observatio
ns and
Results
:
Initial burette reading/
cm3
2
2 2
5
6 5
.
.
5
2 4
0
0 0
0
1 1
.
.
5
0 0
0
0 0
.
.
28.80
3.60
Volume of A used/ cm3
Princes Town West Secondary Unit 2 Chemistry Labs
42 | P a g e
Table 2 Titration of B/X mixture with A, KMnO4
0 4 8
Volume of X added/
3
cm
.
.
.
0 0 0
12.00
0 0 0
2 2
Final burette reading/
cm3
0 2
.
.
20.00
0 5
0 0
Initial burette reading/
cm3
0 6
.
.
8.05
0 5
5 0
Volume of A added/
cm3
↑ Copy and fill out the titration values
Data
Analysis
:
Experiment 1
(a) 25.0 cm3 of B reacted with …………….. cm3 of A.
Show which results you used to obtain this volume of A by placing a tick
under the readings in Table 1.
(b) Calculate how many moles of potassium manganate(VII) were
run from the burette into the conical flask during the titration of B
with A.
Princes Town West Secondary Unit 2 Chemistry Labs
43 | P a g e
(c) Use the half equations for the reaction
MnO4aq- + 8Haq+ + 5e- yields Mnaq2+ + 4H2Ol
Fe(aq)2+ yields Fe(aq)3+ + eand your answer to (b) to calculate the concentration of Fe2+, in mol dm-3,
in B.
Experiment 2
(a) Plot the volume of A against the volume of X.
a. Your scale on the X axis should extend to 30.00 cm3.
(a) Draw the best-fit straight line through the plotted points.
(b) From your graph find the volume of X that reacts with the Fe2+
present in 25.0 cm3 of B.
Graph
Discussion
:
•
•
•
•
Conclusion
:
•
Princes Town West Secondary Unit 2 Chemistry Labs
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Lab# 11
Skills
Assessed:
Date:
O/R/
R
M/M


A/I
P/D
Title
: Chromatography
Theory
In this activity you will be experimenting with a technique called
chromatography which will allow you to visually demonstrate that the
pigment in leaves is a combination of several different coloured pigments.
:
This technique is useful in that it can separate and identify the various
components of mixtures, such as those contained in plant pigments. A
pigment is a substance that absorbs light at specific wavelengths, chlorophyll
is one of these pigments. Its green-yellow in colour is due to the absorption
of red, orange, blue, and violet wavelengths and the reflection of the green
and yellow wavelengths. This occurs when white light (containing all of the
light wavelengths, or the entire spectrum of colours) shines on the leaf
surface, all of the wavelengths are absorbed except for the ones you see,
which are green-yellow, those are the portions of the spectrum being
reflected.
If the conditions are identical, the relative distance moved by a particular
compound is the same from one mixture to another. This is why
chromatography can be used to identify a compound. The actual
identification requires a simple calculation as shown below:
Rf=Distance travelled by componetDistance travelled by mobile phase
It is important to remember that several factors can influence the reliability
of the Rf value, these include humidity, temperature, solvent, pigment extract
preparation, and the amounts of the material present. Values are comparable
only when the extracts are prepared in the same way and the chromatograms
are prepared identically and developed together in the same container.
Acetone is flammable (even the amount found in nail polish remover), keep
it away from sparks or open flames. Wear eye protection, especially if using
pure acetone.
Aim
: To separate the different pigments in plant leaves
Apparatus
: 1. Cone-type (size 4)
Princes Town West Secondary Unit 2 Chemistry Labs
5. capillary tubes
45 | P a g e
and
Material
Procedure
coffee filter paper (or
Whatman #1
chromatography paper)
2. large glass jars
3. acetone
4. distilled water
6. fresh spinach
7. mortar and pestle
8. clean sand
1. Each lab group (or individual if not working in groups) will need 4 strips
of filter paper, approximately 6 inches long and 1 inch wide, 2
chromatography development containers (500 ml beakers or large fruit
:
jars work well), 2 large rubber bands (able to stretch around the vessels
from the mouth to the bottom of the vessel), 2 solvents, water and either
pure acetone, or nail polish remover.
2. Do the following with both fresh spinach leaves; tear leaf material and
place in a glass container, cover with acetone (this should be done the
day before the actual lab activity). An alternative pigment extraction
technique is to use a
mortar and pestle. Place plant material the vessel, add a little clean sand,
some acetone and then grind until a dark green liquid appears. Both
techniques yield very dark pigments with which to work. Be certain to
keep the pigments apart throughout the entire activity.
3. Place one of each solvents (water and acetone, or nail polish remover) in
the chromatography vessels and stretch a rubber band length-wise around
each vessel. The rubber band will be the mechanism for hanging the
chromatography strips.
4. Make a pencil mark on each of the 2 chromatography strips, in the center,
directly above the point of the strip, about 1 inch from the tip of the
paper. Using a capillary tube, or tooth pick, apply the plant pigment to
each filter paper strip. This is done by touching the tooth pick or capillary
tube which has been dipped in the pigment, to the pencil mark. Make an
application, then wave the paper gently to dry it a little before the next
application. Be patient, you will need 12 to 15 applications.
5. By now you should have 2 strips with spinach pigment. Suspend one of
each in each of the chromatography development vessels. You can attach
them with paper clips, or simply fold over a portion of the end and it
should hang in place. The tip of each strip should just touch the solvent.
6. Wait 20 to 30 minutes for the chromatograms to develop. Remove the
chromatograms. Mark with a pencil (NOT a pen) where the solvent
stopped as it moved up the chromatogram. This is called the solvent
front. Mark also where each pigment stopped moving up the
chromatogram. Using the equation below, determine a reference number
for each pigment on the chromatograms. Depending on which
chromatogram you are viewing, you should see greens, yellow/yellow
orange, and red. All measurements should be in mm. (Any material
which did not move from the
pencil dot is insoluble).
Princes Town West Secondary Unit 2 Chemistry Labs
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Observatio
ns and
Results
Note: each pigment has a special name,
green = chlorophyll a or b
: yellow/yellow orange = carotene
red = anthocyanin
brown = xanthophyll
1. Determine the Rf (ratio of fronts) value for each spot using the formula
(remember there may be more than one calculation per spot):
Data
Analysis
:
Rf=Distance travelled by componetDistance travelled by mobile phase
Discussion
:
•
•
•
•
Conclusion
:
•
Princes Town West Secondary Unit 2 Chemistry Labs
47 | P a g e
Lab# 12
Skills
Assessed:
Date:
O/R/
R
M/M

A/I

P/D
Title
: Chromatography
Aim
: To determine the various colours present in food colouring dye and ink pens
using chromatography.
Apparatus
and
Material
1.
2.
: 3.
4.
5.
Procedure
:
8" Aluminum pie plate
Toothpicks
Food coloring
Large Coffee filters
Pencil
6.
7.
8.
9.
Rubbing alcohol (70% Isopropyl Alcohol)
"Expresso" ink pens
Measuring cup
Ruler
1. Measure approximately 1cm from the edge of the coffee filter and mark
eight evenly spaced lines around the filter lightly with a pencil (do not
use ink).
2. Use a toothpick to spot the four food colouring dyes on one-half of the
coffee filter along the pencil mark. On the other half, spot the filter using
the pens. Allow each spot to dry and then re-spot two or three more
times
3. After the coffee filter has been spotted, mark the top of each spot with
your pencil. Below each spot, in pencil, label the colour and if it is pen or
food colouring. (Due to the small space below the spot, it may be easier
to label "p" for pen, "g" for green, etc.)
4. Place the spotted coffee filter "upside down" in the aluminium pie plate.
5. Fill the pie plate (the chromatographic chamber) with rubbing alcohol to
a level just below the spots on the filter.
6. Once the chromatogram has developed and the alcohol travels to the
"top" of the coffee filter, remove the filter from the plate. Using a pencil,
Princes Town West Secondary Unit 2 Chemistry Labs
48 | P a g e
mark the final position of the solvent. Click here to view a video of this
procedure.
7. Next place a pencil mark at the end of each colour. Note that some of the
initial spots separated into multiple colours- be sure to mark each colour
8. Allow the filter to air dry.
9. Determine and record the distance travelled by the mobile phase by
measuring the distance (in mm) from the top of each of the initial spots
(original pencil marks) to the final position of the solvent
10. Determine and record the distance travelled by each colour by measuring
the distance (in mm) from the pencil mark at the top of each of the initial
spots to the mark indicating the end of each colour it produced.
Observatio
ns and
Results
:
1. Determine the Rf (ratio of fronts) value for each spot using the formula
(remember there may be more than one calculation per spot):
Data
Analysis
:
Rf=Distance travelled by componetDistance travelled by mobile phase
Discussion
:
•
•
•
•
Princes Town West Secondary Unit 2 Chemistry Labs
49 | P a g e
Conclusion
:
•
Princes Town West Secondary Unit 2 Chemistry Labs
50 | P a g e
Lab# 13
Skills
Assessed:
Date:
O/R/
R
M/M

A/I

P/D
Title
Theory
: Solvent Extraction
Introduction:
The aim of this experiment is to determine the equilibrium constant, K, for
the distribution of ethanoic acid (CH3COOH, also known as acetic acid)
between two immiscible solvents, diethyl ether and water, using an acid-base
titration. The dynamic equilibrium at the solvent boundary may be
represented by eq. 2
[CH3COOH](aq) k1⇋ k2 [CH3COOH]ether eq.2
: where k1 and k2 are the rate constants of the forward and reverse processes.
At equilibrium the rates of the forward and reverse processes are equal (eq.
3),
k1[CH3COOH](aq)=k2[CH3COOH](ether) eq.3
and the equilibrium constant may then be defined in terms of solute
concentrations or rate constants according to eq. 4.
K=[CH3COOH]ether[CH3COOH]aq=k1k2 eq.4
Aim
To determine the equilibrium constant, K, for the distribution of ethanoic acid
: (CH COOH, also known as acetic acid) between two immiscible solvents, diethyl
3
ether and water, using an acid-base titration.
Apparatus
: 1. Graduated 100 cm3 measuring
Princes Town West Secondary Unit 2 Chemistry Labs
6. Distilled water;
51 | P a g e
2.
3.
4.
5.
and
Material
Procedure
:
7. Diethyl ether;
8. 0.5 M aqueous ethanoic acid;
9. 0.125 M aqueous ethanoic acid;
10. Phenolphthalein indicator
solution.
1. Using a measuring cylinder, add as accurately as possible 50 cm 3 of 0.5 mol dm 3
2.
3.
4.
5.
6.
Observatio
ns and
Results
cylinder;
250 cm3 separating funnel;
Three 100 cm3 conical flasks;
10 cm3 pipette; 50 cm3 burette;
0.1 M sodium hydroxide solution;
aqueous ethanoic acid and 50 cm 3 of diethyl ether into a 250 cm 3 separating
funnel.
Allow the mixture to stand for at least twenty minutes, shaking occasionally
(remember to release the pressure after shaking by inverting the funnel, holding
on to the stopper and opening the tap).
Run off the lower (aqueous) phase into a clean 100 cm 3 conical flask, making
sure no ether is drained off. Now run off the interface portion and discard it and
leave the ether layer phase in the separating funnel.
Pipette 10 cm3 of each phase into separate 100 cm 3 conical flasks and add a few
drops of phenolphthalein indicator. Titrate both solutions with 0.1 mol dm -3
sodium hydroxide solution until the solution retains a permanent pink colour.
Repeat the titrations with two further 10 cm 3 aliquots.
Repeat steps 1-3 using 0.125 mol dm -3 aqueous ethanoic acid in place of the 0.5
mol dm-3 solution.
:
Data
Analysis
Treatment of Results
1. Write a balanced equation for the reaction between ethanoic acid and sodium
hydroxide.
2. From the volumes of sodium hydroxide solution required to neutralise the
ethanoic acid, calculate the number of moles of ethanoic acid in each 10 cm 3
aliquot you titrated and, hence, evaluate the ethanoic acid concentration for each
:
solution.
3. Using the ethanoic acid concentrations you have determined, evaluate the
equilibrium constant, K, using eq. 4 for both initial ethanoic acid
concentrations.
4. Do the values of K obtained using 0.5 mol dm -3 and 0.125 mol dm -3 ethanoic
acid differ? Is this to be expected?
Discussion
:
•
•
Conclusion
:
•
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Lab # 14
Skills
Assessed:
Date:
O/R/
R
M/M
A/I
P/D

Title
: Plan Design: Analytical Chemistry
Case
Contamination of drinking water supplies from industrial waste is a result of
various types of industrial processes and disposal practices. Industries that
use large amounts of water for processing have the potential to pollute
: waterways through the discharge of their waste into streams and rivers, or by
run-off and seepage of stored wastes into nearby water sources. From this
information, is it possible to determine if effluents from ISPAT is sufficient
to cause adverse effects on the quality of drinking water.
Hypothesis
:
Aim
:
:
1.
Apparatus
and
Material
:
Procedure
:
2.
1.
2.
3.
4.
Variables
:
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Expected
Observatio
ns and
Results
:
Data
Analysis
:
1.
2.
Precaution
s
:
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Lab # NA
Skills
Assessed:
Date:
O/R/
R
M/M

A/I
P/D
Title
: Organic Chemistry
Aim
: To distinguish between alkanes and alkenes
Alkanes are saturated compounds which are relatively inert. They undergo
very few reactions which include combustion, cracking and free radical
substitution with halogens such as chlorine and bromine. Substitution
reaction requires the presence of UV light which is needed to split the inert
halogens to from the reactive free radicals.
Alkenes on the other hand, are unsaturated compounds which takes part in a
wide range of addition reactions due to the presence of the double bond in
alkene molecules. The double bonds in alkenes are an electron rich centre
which allows it to undergo electrophilic reactions and react with oxidizing
agents.
Theory
Alkenes decolorize a solution of bromine in 1, 1, 1 trichloroethane
:
CH3CCl3
C6H12 +
Hexene
Br2
C6H12Br2
reddish – brown
colourless 1,2 dibromohexane
Alkenes decolorize an acidified solution of potassium manganate (VII)
KMnO4/H+
C6H12 +
Hexene
C6H12(OH)2
colourless hexane – 1,2 - diol
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Apparatus
and
Material
Procedure
:
1. 1 % bromine in 1,1,1 trichloroethane
2. 0.02 mol dm-3 KMnO4
3. Dilute H2SO4
4. Samples of Hexane and
Hexene labelled A and B
5. Test tubes
1. To 2 cm3 of sample A in a test tube, bromine was added drop by
drop. Solution was stirred and observations were made and recorded.
:
2. A few drops of dilute H2SO4 was added to 1 cm3 of KMnO4. The
acidified KMnO4 was then added drop by drop to another test tube
containing 2 cm3 of sample A. The mixture was stirred and
observations were made and recorded.
3. Steps 1 and 2 were then repeated with sample B
Table 1
Observation
s and
Results
Data
Analysis
and
Interpretati
on
Observation table
Step
Sample A
Sample B
: On addition of Bromine
Solution turns
colourless
No visible reaction
On addition of acidified
KMnO4.
Solution turns
colourless
No visible reaction
1. Deduce which sample is an alkane and which is an alkene
:
Sample A is an Alkene and Sample B is an Alkane.
2. Outline the mechanisms for any reactions which occurred.
Alkenes contain a double bond, which is an electron rich centre, and
in the presence of bromine in 1, 1, 1-trichloroethane, Br2 is added
across the double bond, causing decolourization of the bromine
solution from brown to colourless, via an addition reaction.
CH3CCl3
C6H12 +
Hexene
Br2
reddish – brown
Princes Town West Secondary Unit 2 Chemistry Labs
C6H12Br2
colourless 1,2 dibromohexane
57 | P a g e
Alkenes react with potassium manganate(VII) solution. If the
potassium manganate(VII) solution is acidified with dilute sulphuric
acid, the purple solution becomes colourless. Manganate(VII) ions
are a strong oxidising agent, and they will oxidise the hexene to a
diol, while the manganate(VII) ions are reduced to manganese(II)
ions.
Manganate (VII) ions are purple in solution whereas manganese(II)
ions are colourless, and hence there will be a colour change from
purple to colourless in the presence of the alkene.
KMnO4/H+
C6H12 +
C6H12(OH)2
Hexene
colourless hexane – 1,2 – diol
Neither of these reactions will occur with the alkane, and so there
will be no colour change in the presence of the alkane.
Conclusion
: Sample A is Hexene and Sample B is Hexane
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Lab # NA
Skills
Assessed:
Date:
O/R/
R
M/M

A/I
P/D
Title
: Carbonyl Compounds
Aim
: Investigating Carbonyl Compounds
Aldehydes and ketones are carbonyl compounds which contains the
Theory
carbonyl group
. Aldehydes have a single alkyl or acyl group attached
to the carbon atom whilst ketones have two. They both react with 2, 4
dinitrophenylhydrazine (2,4 – DNPH) to give orange precipitates.
: Mild oxidising agents such as Tollen’s and Fehling’s reagents can oxidise
aldehydes but not ketones. Hence this reaction can be used to distinguish the
both of them.
Tollen’s reagent forms a silver mirror on the wall of the test tube and
Fehlings solution gives a red-brown precipitate of Copper (I) Oxide.
Three samples are given, two of which are carbonyl compounds, one is an
aldehye and the other is a ketone.
Apparatus
and
Material
Procedure
:
1. Samples B, C and D
2. 2, 4 – DNPH (dissolve 2 g of 2, 4DNPH in 4 cm3 of conc. H2SO4, 30
cm3 of methanol and 10 cm3 of
water.
:
1. 3 cm3 of 2,4 – DNPH was added to a few drops of sample B in a test
tube and observations were made and recorded.
Princes Town West Secondary Unit 2 Chemistry Labs
3. Fehling’s reagent
4. Aqueous NH3 and
AgNO3
5. Measuring cylinders
6. Test tubes
59 | P a g e
2. To 3 cm3 of AgNO3 in a test tube, ammonia solution was then added
dropwise, while shaking the solution until the precipitate formed redissolved. A few drops of sample B was then added to this tube
(Tollens Test) and observations were made and recorded.
3. A few drops of sample B was added to Fehlings reagent in a test tube
and the tube was gently heated. Observations were recorded.
4. Steps 1-3 was then repeated for Sample C and D.
Table 1
Observation
s and
Results
Data
Analysis
and
Interpretati
on
:
Observations
Solution added
Sample B
Sample C
Sample D
2,4- DNPH
Orange
precipitate
formed
Orange
precipitate
formed
No visible reaction
AgNO3 and NH3
No visible
reaction
Silver
mirror
formed on
test tube
No visible reaction
Fehlings reagent
No visible
reaction
Redbrown
precipitate
No visible reaction
1. Deduce which of the samples are carbonyl compounds.
:
Sample B and Sample C are both Carbonyl compounds since they
both reacted with 2, 4 dinitrophenylhydrazine to give an orange
precipitate.
2. Deduce which of the samples is an aldehyde
Sample C is an aldehyde since it was oxidised by both Tollen’s
reagent and Fehlings reagent where it formed a silver mirror and a
red- brown precipitate respectively. Mild oxidising agents can
oxidise aldehydes, but not ketones.
Tollens Test:
CH3CHO(l) + 2Ag+(aq) + H2O(l) CH3COOH (aq) + 2Ag(s) + 2H+(aq)
Fehlings reagent gives a red brown precipitate of copper (I) Oxide:
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CH3CHO(l) + 2Cu2+(aq) + 2H2O(l) CH3COOH (aq) + Cu2O(s) + 4H+(aq)
3. Deduce which sample is a ketone:
Sample B is the ketone, since it gave an orange precipitate with 2, 4
dinitrophenylhydrazine, which means that it is a carbonyl compound,
but it showed no reaction with the weak oxidising agents Tollens
reagent and Fehlings reagent.
These two tests are used to distinguish between an aldehyde and a
ketone.
Discussion
•
:
•
•
•
Conclusion
:
Tollens reagent and Fehlings reagent are weak oxidising agents
Can be used to distinguish between aldehydes and ketones
Shows not reaction with ketones
Gives a silver mirror test and red-brown precipitate with aldehydes
Sample B is the ketone and Sample C is an aldehyde.
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Lab # NA
Skills
Assessed:
Date:
O/R/
R
M/M

A/I
P/D
Title
: Organic Compounds
Aim
: To investigate the oxidation of alcohols
Primary alcohols are readily oxidised to carboxylic acids by a variety of
oxidising agents such as acidified potassium dichromate (VI).
Theory
Cr2O72- (aq) + 14H+(aq) + 6e:
2Cr3+ (aq) + 7H2O(l)
Orange
green
Primary alcohols are firstly oxidised to aldehydes and then to carboxylic
acids. Secondary alcohols are oxidised to ketones and tertiary alcohols are
resistant to oxidation.
Apparatus
and
Material
:
Procedure
:
1. Ethanol
2. 5 g dm-3 Potassium dichromate
(VI) solution
3. Test tubes
4. Water bath
5. Concentrated sulphuric
acid
6. Measuring cylinders
7. Bunsen burner and
tripod stand
1. 5 cm3 of ethanol was placed in a test tube.
2. To this tube, 2 cm3 of potassium dichromate (VI) solution was added,
followed by 3-4 drops of concentrated H2SO4
3. The tube containing this mixture was then placed in a water bath at
60 ºC and any colour change was recorded.
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4. The mixture was then allowed to cool and the scent of vinegar was
identified coming from the reaction mixture.
Table 1: Observations
Observation
s and
Results
On addition of potassium dichromate (VI)
solution
: On addition of concentrated H2SO4 and heat
Solution in test tube turned orange colour
Colour change from orange
Light green
After cooling
yellow
blue
The scent of vinegar was noted and two layers
were present in the tube, one clear and the
other cloudy
1. Write equations for any reactions that occurred
Data
Analysis
and
Interpretati
on
An acidified dichromate ion readily accepts electrons and this makes it a
powerful oxidising agent.
Cr2O72- (aq) + 14H+(aq) + 6eOrange
:
2Cr3+ (aq) + 7H2O(l)
green
Initially, the colour of the solution is orange due to the dichromate ions. On
oxidation of ethanol, which is a primary alcohol, an aldehyde is formed
firstly.
Cr2O72-/H+
CH3CH2OH(aq)
CH3HC=O + 2H+ + 2eThe aldehyde is further oxidised to a carboxylic acid, ethanoic acid.
CH3HC=O + H2O
CH3COOH + 2H+ + 2e-
2. Describe how this experiment can be scaled up to obtain a pure
sample of ethanoic acid.
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Discussion
:
•
Discuss the principles on which the breathalyser test is based?.
Potassium dichromate, K2Cr2O7, is a yellow-orange compound. When
alcohol vapour makes contact with the yellow-coated crystals, the colour
changes from yellow to green. The degree of the colour change is directly
related to the level of alcohol in the suspect's breath. The oldest breathalyzer
models pass breath through a solution of potassium dichromate, which
oxidizes ethanol to acetic acid, changing color in the process
Cr6+
Orange
Conclusion
Cr3+
Green
:
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Lab # NA
Skills
Assessed:
Date:
O/R/
R
M/M

A/I
P/D
Title
: Organic Compounds
Aim
: To investigate the formation of esters
When an alcohol reacts with a carboxylic acid in the presence of
concentrated sulphuric acid, an ester is formed.
Theory
:
RCOOH(l) + R OH(l)
RCOOR
(l)
+ H2O (l)
The ester is recognised by its distinctive fruity smell.
Apparatus
and
Material
Procedure
Ethanol
Glacial ethanoic acid
Cold water
Bunsen burner and tripod
Boiling tube
6. Concentrated sulphuric
acid
7. Measuring cylinders
8. Beaker
9. Water bath
:
1.
2.
3.
4.
5.
:
1. 5 cm3 of ethanol and 5 cm3 of ethanoic acid were placed in a boiling
tube.
2. To this tube, 1 cm3 of concentrated H2SO4 was then added.
3. The tube containing this mixture was then placed in a water bath at
60 ºC and observations were made.
4. After heating the mixture in the water bath for 10 minutes, it was
then poured into a beaker containing ice cold water. Observations
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were made and recorded.
Table 1: Observations
Observation
s and
Results
On mixing ethanoic acid and ethanol
: On addition of concentrated H SO and heat
2
4
On pouring mixture in beaker containing
ice cold water
Data
Analysis
and
Interpretati
on
No visible reaction
No visible reaction
Two distinct layers were visible. The top layer
was insoluble and cloudy and a sweet fruity
smell was emitted.
1. Write equations for any reactions that occurred
: Ethanol and Ethanoic acid react together to from an ester, ethyl ethanoate
CH3COOH(l)
+ CH3CH2OH(l)
CH3COOHCH2CH3(l)
+ H2O(l)
2. What is responsible for the smell obtained.
The formation of the ester, ethyl ethanoate, which has a fruity smell, is the
compound that is responsible for the fruity smell emitted during the reaction.
3. Why is the reaction mixture poured into cold water?
Discussion
•
•
:
Conclusion
•
Ethanoic acid + ethanol
ethyl ethanoate + water
ethyl ethanoate is a volatile ester with a characteristic fruity smell.
Ester formation is an example of a condensation reaction, where
there is elimination of water, and formation of the ester bond.
:
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Lab # 15
Skills
Assessed:
Date:
O/R/
R
M/M

A/I

P/D
Title
: Simple and Fractional Distillation
Aim
: To compare the efficiency of separation of an ethanol- water mixture by
simple and fractional distillation.
Theory
Simple distillation is used to separate volatile liquids from non- volatile ones
with different boiling points. If the boiling points difference between two
: liquids is less than 60 degrees, then fractional distillation is used instead.
Ethanol and water are miscible solvents whose boiling points are 78ºC and
100ºC respectively, and hence fractional distillation is more appropriate for
their separation.
Apparatus
and
Material
:
Procedure
:
1. Simple and Fractional distillation
apparatus
2. 50-50 mixture of ethanol and water
3. Thermometer
4. 50 cm3 measuring
cylinder
5. Anti-bumping granules
6. Hot plate
1. The class was divided into two groups. One group carried out simple
distillation and the other group carried out fractional distillation. The
information and data obtained by both groups were then shared
within the two groups.
2. The distillation apparatus was set up, using a measuring cylinder as
the collecting vessel.
3. 50 cm3 of ethanol- water mixture together with some anti-bumping
granules were added to the distilling flask. The flask was then
attached to the rest of the apparatus.
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4. The distilling flask was placed on a hot plate
5. The temperature was recorded when the first drop of distillate came
out.
6. The temperature was recorded for every 3 cm3 of distillate that came
out
7. Distillation was stopped when there was about 5 cm3 of mixture in the
distilling flask.
Observatio
ns and
Results
:
Table 1 : Temperature readings for distillate collected during fractional distillation
Volume of Distillate / cm 3
Temperature / ºC
1st drop
03
06
09
12
15
18
21
24
27
30
Table 2 : Temperature readings for distillate collected during simple distillation
Volume of Distillate / cm 3
Temperature / ºC
03
06
09
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12
15
18
21
24
27
30
1. Plot graph of temperature of distillate against volume of distillate for
simple and fractional distillation on the same axes.
Graph
Data
Analysis
:
1. Use your graph to deduce which type of distillation separates the
mixture better
2. Explain graph
Data
Analysis and
:
Interpretati
on
1. Write a balanced equation for the reaction between hydrochloric acid
and sodium hydroxide
Discussion
•
How would heating more rapidly affect distillation?
•
What effect would using a longer column have on fractional
distillation?
Conclusion
:
:
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Lab # 16
Skills
Assessed:
Date:
O/R/
R
M/M

A/I
P/D
Title
: Organic Compound
Aim
: To analyse substance X4
Theory
: Sample X4 is an organic compound which contains four Carbon atoms.
Apparatus
and
Material
Procedure
:
:
1.
2.
3.
4.
Sample X4
Bromine solution
Solid Na2CO3
Test tubes and test tube racks
5. 2, 4 – DNPH
6. Bench reagents :
AgNO3(aq), NH3(aq),
NaOH(aq), I2(aq)
7. Measuring cylinder
1. Bromine solution was added dropwise to 3 cm3 of sample X4 and
observations were made and recorded
2. Solid Na2CO3 was added to 3 cm3 of sample X4 and observations were
made and recorded
3. 2, 4 – DNPH was added dropwise to 3 cm3 of sample X4 and
observations were made and recorded
4. Ammonia solution was added dropwise to 4 cm3 of AgNO3 until the
precipitate that formed just re dissolved. (Tollens Reagent). A few
drops of Sample X4 was then added to this reagent. Any observations
made were recorded.
5. 2 cm3 of Iodine solution was added to 3 cm3 of sample X4 . NaOH was
then added dropwise while gently shaking. Any observations made
were recorded.
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Table 1: Observations and Inferences made during the experiment
Tests
Observations
Inferences
On addition of Bromine
solution
Observatio
ns and
Results
:
On addition of Solid
Na2CO3
On addition of 2,4
DNPH
On addition of Tollens
Reagent
On addition of Iodine
Solution
Discussion
:
•
Conclusion
:
•
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Lab # 17
Skills Assessed:
Date:
O/R/
R
M/M
A/I
P/D
Title

: Plan Design: To determine the acidity / pH of a soil sample
Soil pH is a measure of hydronium ion (H3O+, or more commonly the H+) activity
in the soil solution. Soil pH influences many facets of crop production and soil
chemistry, including availabilities of nutrients and toxic substances, activities and
nature of microbial populations, and activities of certain pesticides. Soils with pH
values below 7 are referred to as "acid" and those with pH values above 7 as
"alkaline"; soils at pH 7 are referred to as "neutral." Most crops grow best if the
soil pH is between 6.0 and 7.5.
Case
:
Mr. Smith, a farmer, wants to increase his yield of vegetables, but of lately, he
finds that his plants are not thriving well. His neighbour tells him that his soil
may be too acidic for the plants to grow well, and suggests that he test the pH of
his soil to confirm.
Plan and Design an experiment to test for the pH of the soil, using a pH meter.
Apparatus
and
Material
Procedure
:
:
1.
2.
3.
4.
pH meter
Electronic balance
Paper cups
Standard buffer solutions of pH 2, 4, 7
and 9 for calibrating pH meter
5.
6.
7.
8.
Pipettes
Soil sample
Deionized water
Stirrer
1. Calibrate the pH meter over the appropriate range using the standard
buffer solutions.
2. Weigh 5 g of sieved, air dried soil sample and place into a paper cup.
3. Add 5 ml deionized water to the sample of soil in the paper cup
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4. Stir the sample for a minute, and then leave to settle for 30 minutes to
form a slurry
5. After formation of slurry, place electrodes of the pH meter into the slurry
and read the pH, ensuring that the electrodes tips are in the slurry.
6. Repeat the above procedure at least twice for accuracy.
Observatio
ns and
Results
Discussion
Conclusion
Table 1 : Recorded pH of soil sample
Samples
:
:
pH
Sample 1
Sample 2
Sample 3
•
Which type of water (distilled, deionized, tap water) is preferred, and give
reasons why?
•
Theoretically, if the pH of a soil sample is 2, and you want to obtain the
optimum pH for best growth of crop, that is, a pH between 6.0 and 7.5,
what procedures can be done to this soil sample in order to achieve this
optimum pH?
•
Give two precautions that should be undertaken when carrying out your
experiment?
:
Lab # NA
Skills Assessed:
Date:
O/R/
R
M/M
A/I
P/D

Title
: Plan Design: To purify a sample of rock salt
Case
: Rock salt, also known as halite, or impure NaCl, is typically formed by the
evaporation of salty sea water which contains dissolved Na+ and Cl- ions, as well
as other impurities such as potassium and sulphates. Rock salt is also applied to
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road beds in cold climates to help reduce the freezing point of water on the road,
and since saline has a lower freezing point that water, putting rock salt on ice will
cause it to melt.
Table salt is essential for human life. A large amount of the commercially mined
rock salt is prepared for human consumption. Plan and design an experiment to
obtain pure NaCl, or table salt, from a sample of impure rock salt. Include how
you would be able to find the percentage of mass of salt crystals recovered from
the sample of rock salt.
Apparatus
and
Material
:
Procedure
:
1.
2.
3.
4.
Sample of rock salt
Balance / Scale
Filter paper and funnel
Bunsen burner
5.
6.
7.
8.
Conical flasks
Distilled water
Ice bath
Beakers
1. Weigh 10 g of the rock salt using the electronic balance
2. Place this sample in a beaker, and then dissolve it in a small amount of hot
water, while stirring the mixture
3. Weigh a sheet of filter paper and record this value
4. After dissolving the sample of rock salt, then filter the mixture, collecting
the filtrate in a conical flask
5. Allow the filtrate in the conical flask to cool by placing in into an ice bath,
to recrystallize the NaCl
6. Filter the crystals with distilled water to allow for any soluble impurities
to be removed
7. Wash, dry and weigh the crystals within the filter paper.
Observatio
ns and
Results
Data
Analysis
Table 1 : Mass of rock salt
Mass of rock salt / g
:
Table 2 : Mass of purified salt
Mass of filter paper and crystals / g
Mass of filter paper / g
Mass of crystals / g
:
1. Mass of purified crystals (g)
= mass of filter paper and crystals (g) – mass of filter
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paper (g)
2. Percentage by mass of salt crystals recovered from the sample of rock salt
= mass of purified crystals (g)mass of rock salt (g) x
100
Discussion
:
Conclusion
:
•
Lab # 18
Skills Assessed:
Date:
O/R/
R
M/M

A/I

P/D
Title
: Analytical Chemistry Back Titration
Aim
: To determine the mass of 2-ethanoylhydroxy-benzoic acid in a commercial brand
of an aspirin tablet by back titration
Aspirin is an analgesic compound which has to ability to reduce inflammation and
hence acts as both a pain killer and a fever reducer. The active ingredient in
aspirin tablet is 2-ethanoylhydroxy-benzoic acid (acetylsalicylic acid), the ester
linkage in aspirin is hydrolyzed/broken by alkalis to form ethanoate ions and 2hydroxybenzoate (salicylate) ions.
Theory
: CH COOC H COOH + 2OH3
6 4
CH3COO- + HOC6H4COO- + H2O
An aspirin tablet can be hydrolyzed with excess sodium hydroxide and then back
titrated with hydrochloric acid. The amount of alkali used for the hydrolysis can
then be calculated and from this information, the mass of 2-ethanoylhydroxybenzoic acid in an aspirin tablet can be determined.
Apparatus
and
Material
:
1. Aspirin tablets
2. Standard 0.2 mol dm-3 NaOH
3. Standard 0.1 mol dm-3 HCl
Princes Town West Secondary Unit 2 Chemistry Labs
5. 25 cm3 pipette
6. 3 conical flasks
7. Bunsen burner
76 | P a g e
4. 50 cm3 burette
Procedure
:
8. Phenolphthalein indicator
1. 25 cm3 of NaOH was pipetted into a conical flask and one aspirin tablet
was added to this flask. The solution was then warmed gently to allow the
tablet to dissolve.
2. The solution was then cooled, and three drops of Phenolphthalein indicator
was then added to it.
3. This solution was then titrated with hydrochloric acid.
4. Steps 1 to 3 were then repeated until accurate results were obtained.
Table 1: Volume of HCl used in the titration
Rough
Observation
s and
Results
:
Accurate
Final burette reading / cm3
8.6
17.2
25.8
34.3
Initial burette reading / cm3
0.0
8.6
17.2
25.8
Volume of HCl used / cm3
8.6
8.6
8.6
8.5
25 cm3 of aspirin and NaOH required 8.6 cm3 of HCl in the titration.
Discussion
:
1. Write a balanced equation for the reaction between hydrochloric acid and
sodium hydroxide
2. Calculate the number of moles of NaOH in the 25 cm3 of alkali used.
3. F ind the number of moles of HCl used in the titration
4. How many moles of NaOH reacted with HCl in the titration
5.
How many moles of NaOH reacted with the 2-ethanoylhydroxy-benzoic
acid in one aspirin tablet.
6. Calculate the number of moles of 2-ethanoylhydroxy-benzoic acid in one
aspirin tablet.
7. Determine the mass of 2-ethanoylhydroxy-benzoic acid in one aspirin
tablet.
Conclusion
:
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Lab # 19
Skills
Assessed:
Date:
O/R/
R
M/M

A/I

P/D
Title
: Environmental
Aim
: To test for pollutants in water
Pollutants found in water include cyanide, lead (II) ions, nitrates and
phosphates. Cyanide is converted to thiocyanate when it reacts with sulphur.
This ion is found in effluents from mining and industrial factories. Certain
pesticides also contain thiocyanate ion as the main ingredient. Phosphates are
nitrates are present in fertilizers and detergents, and these can also pollute the
waterways.
Theory
:
Carry out the following procedure to test for SCN-, NO3-, PO43- and Pb2+.
SCN- gives a blood red colour on addition of aqueous iron (III) nitrate.
PO43- gives a bright yellow precipitate when warmed with ammonium
molybdate
NO3- is identified via the brown ring test
A white precipitate is formed with Pb2+ on addition of hydrochloric acid.
Apparatus
and
Material
:
Procedure
:
1. Samples of Polluted water P, Q and
R
2. 0.1 mol dm-3 iron (III) nitrate
solution
3. 0.1 mol dm-3 ammonium molybdate
4. Solid iron (II) sulphate
5. Bunsen burner
6. spatula
7. Conc. H2SO4
8. Conc. HNO3
9. Bench HCl and H2SO4
10. Test tubes
11. Water bath
1. Iron (III) Nitrate was added drop by drop to 2 cm3 of sample P in a
test tube. Observations were made and recorded.
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2. 2 cm3 of sample P in a test tube was acidified with dilute H2SO4. Half
a spatula of solid iron (II) sulphate was then added to the acidified
sample.
3. To this acidified sample of P, 0.5 cm3 of Conc. H2SO4 was then
carefully added, by letting it flow down the side of the test tube. The
mixture was then left undisturbed until two separate layers were
formed within the test tube. Observations were made ad recorded.
4. 2 cm3 of sample P in a test tube was acidified with Conc. HNO3. A
little amount of ammonium molybdate was then added and the tube
was then gently warmed in a water bath. Observations were made and
recorded.
5. Dilute HCl was added to 2 cm3 of sample P in a test tube. The
mixture was then heated for one minute and then allowed to cool.
Any observations were recorded.
6. Steps 1-5 were then repeated for both sample Q and R
Table 1 : Observations made during the experiment for all three samples P, Q
and R
Observations with:
Observatio
ns and
Results
:
Sample
s
Fe(NO3)3(aq)
Fe2+(aq)/conc.
H2SO4
(NH4)2
MoO4(a
HCl (aq)
q)
P
Q
R
Data
:
Analysis and
Interpretati
on
1. Deduce which of the samples of water are polluted with:
Thiocyanate ions
•
Nitrate ions
•
Phosphate ions
•
Lead (II) ions
•
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Justify your answers.
Conclusion
:
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Lab # NA
Skills
Assessed:
Date:
O/R/
R
M/M

A/I

P/D
Title
: Plan and Design : Organic Chemistry
Aim
: Organic
Case
Mr. Smith wants to buy a new car. He has a choice of vehicles which run on
leaded gasoline, unleaded gasoline, compressed natural gas, and diesel. His
: environmentally conscious friend suggests he buys a car which contributes to
the least amount of pollution. Suggest which fuel is most environmentally
friendly and plan and design an experiment to test your suggestion.
1.
Apparatus
and
Material
:
Procedure
:
2.
1.
2.
3.
4.
5.
6.
Observatio
ns and
Results
:
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Data
Analysis and
:
Interpretati
on
Discussion
:
•
•
Conclusion
:
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Lab # 20
Skills
Assessed:
Date:
O/R/
R
M/M

A/I

P/D
Title
: Plan and Design : Analytical Chemistry (Gravimetric)
Aim
:
Caesium nitrate, CsNO 3, decomposes on heating.
Case
The decomposition is represented by one of the following equations.
4CsNO3(s)  2Cs2O(s) + 4NO 2(g) + O2(g)
2CsNO3(s)  2CsNO2(s) + O2(g)
You are to devise a method of heating the solid
nitrate, collecting the gas given off and measuring its
volume.
:
From the experimental results you are to determine
which is the correct equation for the decomposition.
Information that may be used to prove your plan and design.
The molar volume of gas,
Vm,
is 24.0 dm 3 mol–1 under room conditions.
Nitrogen dioxide, NO 2, a toxic gas, is soluble in water.
Oxygen, O2, is not soluble in water.
[Ar; Cs, 133.0; N, 14.0; O, 16.0.]
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1.
Apparatus
and
Material
:
Procedure
:
2.
1.
2.
3.
4.
5.
6.
Diagram
:
Observatio
ns and
Results
:
Data
Analysis and
:
Interpretati
on
Discussion
:
•
•
Conclusion
:
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