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510600412-CAPE-Chemistry-Labs

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Kelliann George
Chemistry
Unit 1
Lab#
Skill:
Date
Caribbean Advanced Proficiency Examination
Chemistry Labs
Candidate name: Bibi Assiya Hamid
Candidate No:
School:
St. Stanislaus College
School Code:
090047
Year of Exam:
2021
Teacher:
Sir. Damian La Rose
Kelliann George
Chemistry
Unit 1
Lab#
Skill:
Date
TOPIC: Volumetric analysis
AIM: To determine the unknown concentration of sodium hydroxide solution
BACKGROUND INFORMATION:
MATERIALS/APPARATUS:
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2 beakers (100 mL)
Sodium hydroxide (NaOH)
1 Burette (50 mL)
2 250 mL Erlenmeyer Flask
Wash bottle
Distilled water
burette clamp stand
Methyl orange indicator
White tile
0.2 M Sulphuric acid solution
METHOD:
1. A clean burette was rinsed with distilled water then with acid solution.
2. The burette was mounted on clamp stand.
3. Burette was then filled with acid solution to the zero mark (ensure no air bubbles are
present).
4. 20 mL of the basic solution was pipetted into a clean conical flask
5. 2-3 drops of methyl orange was placed into the flask with acid.
6. Titration was left to occur (allow the acid solution from the burette to run into the base
solution in the flask) until the first permanent colour change was observed.
7. Steps 4-6 was repeated three times to ensure that the titer value differs no more than 0.1
mL.
DIAGRAM:
Bibi Assiya Hamid
Chemistry
Unit 1
Lab#
Skill:
Date
RESULTS/OBSERVATIONS:
Burette Reading
Initial reading
Final reading
Titre
Trial
0.00
5.50
5.50
Titration
Titration 1
Titration 2
5.50
11.50
11.50
17.3
6.00
5.80
CALCULATIONS:
DISCUSSION:
PRECAUTIONS:
1. Ensure air bubbles are not present in pipette
2. Keep chemical bottles off the bench and do not contaminate pipettes.
SOURCE OF ERROR:
Titration 3
17.30
23.00
5.7
Bibi Assiya Hamid
Chemistry
1.
2.
CONCLUSION:
REFERENCES:
TOPIC: Redox titration
Unit 1
Lab#
Skill:
Date
Bibi Assiya Hamid
Chemistry
Unit 1
Lab#
Skill:
Date
AIM: To standardized a solution of potassium permanganate.
BACKGROUND INFORMATION:
Potassium manganate (VII) (potassium permanganate, KMnO4) solution can be standardised by
titration against a standard solution of ammonium iron (II) sulfate solution. The iron (II) solution
is measured by use of a pipette, whilst the potassium manganite (VII) solution is placed in a
burette. The titration is carried out under acidic conditions, so the pipetted Fe+2 solution is
acidified by addition of about 10 cm3 of dilute sulfuric acid before commencement of the
titration. The reaction is represented by the equation:
MnO + 8H+ + 5Fe+2  Mn+2 + 5Fe+3 + 4H2O
No indicator is needed, as the manganite (VII) ions are decolourised in the reaction until the endpoint, when a pale pink colour persists.
MATERIALS/APPARATUS:
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Potassium manganite (VII) solution
0.1 M ammonium iron (II) sulfate solution
1.5 M sulfuric acid solution
Deionised (or distilled) water
Safety glasses
Pipette (25 cm3)
Pipette filler
Burette (50 cm3)
Filter funnel
Graduated cylinder (100 cm3)
Conical flask (250 cm3)
White tile
White card
Retort stand
Boss-head
Clamp
Beakers (250 cm3)
Wash bottle
METHOD:
Bibi Assiya Hamid
Chemistry
Unit 1
Lab#
Skill:
Date
DIAGRAM:
RESULTS/OBSERVATION
Initial
Final
Titre
Trial
0.00
13.8
13.8
1
13.8
27.5
13.7
2
27.5
41.1
13.6
3
0.0
13.6
13.6
Bibi Assiya Hamid
Chemistry
Unit 1
Lab#
Skill:
CALCULATIONS:
DISCUSSION:
PRECAUTIONS:
1.
SOURCE OF ERROR:
1.
REFERENCES:
TOPIC: Molar Enthalpy
AIM: To determine the enthalpy change for the displacement reaction:
Date
Bibi Assiya Hamid
Chemistry
Unit 1
Lab#
Skill:
Date
Zn(s) + Cu2+(aq) → Zn2+(aq) + Cu(s)
BACKGROUND INFORMATION:
MATERIALS/ APPARATUS:
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Goggles
Bench mat
25cm3 pipette
Pipette filler
Polystyrene cup with lid
Weighing bottle
Spatula
Balance
Thermometer
Stop clock
Zinc powder
1.0M copper(II) sulphate solution
METHOD:
1. 25cm3 of CuSO4 (aq) was measured with a pipette and released into the polystyrene cup.
2. 5g of zinc was weighed in the weighing bottle.
3. The thermometer was placed through a hole in the lid, stirred and the temperature was
recorded for every half minute for 2½ minutes in the table below.
4. The zinc was added to the cup at precisely 3 minutes.
5. Stirring continued and the temperature was recorded for an additional 6 minutes in the
table below.
DIAGRAM:
RESULTS/ OBSERVATION:
Time (minutes)
Temperature(oC)
Time (minutes)
Temperature (oC)
Bibi Assiya Hamid
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
4.5
Chemistry
Unit 1
30o
30o
30o
30o
30o
30o
not done
Lab#
Skill:
5.0
5.5
6.0
6.5
7.0
7.5
8.0
8.5
9.0
9.5
Date
30o
31.5o
32.5o
33.5o
35.5o
36.5o
37.2o
38o
38.2o
39.2o
39.5
39.9
40.1
40.2
40.1
40.05
40
CALCULATIONS:
DISCUSSIONS:
CONCLUSION:
REFERENCES:
TOPIC: Testing for Vitamin C.
STATEMENT OF PROBLEM: With the covid pandemic present, doctors are advising that
sanitation is important as well as strengthening our immune system with increase intake of
Bibi Assiya Hamid
Chemistry
Unit 1
Lab#
Skill:
Date
Vitamin C. As the health officer, you are required to advise the general populace on the better
source of Vitamin C.
HYPOTHESIS: Compared to emergency vitamin C powder, vitamin C tablets are the best
source of vitamin C because it retains most of the vitamin C from its source.
AIM: To compare and determine the source of Vitamin C that will best serve to strengthen the
immune system against the covid- 19 virus.
BACKGROUND INFORMATION:
Vitamin C is a vitamin found in various foods and sold as a dietary supplement. It is involved in
many body functions including; Formation of collagen, absorption of iron, the proper functioning
of the immune system, wound healing and the maintenance of cartilage bones and healing
vitamin c is an antioxidant. Antioxidants like vitamin c acts as a first target of reactive molecules
like oxygen or iodide. This protects molecules critical to our health .The vitamin protects iodine
from reacting with starch. Once all the vitamin c has reacted any additional iodine reacts with
starch and blue black color is seen.
MATERIALS/ APPARATUS:
● Vitamin C Tablet
● Emergency vitamin C powder
● Burette
● 6 test tubes
● Pipette
● Knife
● Beaker
● Test tube rack
● Starch solution
● Iodine solution
METHOD:
1. Gather all equipment’s and ensure they are washed.
Bibi Assiya Hamid
Chemistry
Unit 1
Lab#
Skill:
Date
2. Crush the 2 tablets separately after weighing them.
3. Dissolve tablets and emergency powder in two different volumetric flasks with 200ml of
distilled water.
4. Mix starch solution and iodine solution in two different conical flasks.
5. Zero burette with iodine solution.
6. Combine 5ml of the dissolved emergency vitamin C powder with distilled and starch
solution in a volumetric flask.
7. Burette iodine solution into the volumetric flask swirling until the first permanent blue
black color change appears through out the entire solution.
8. Record the initial and final titration graduation. Repeat two more times with the same
mixture. And then three more times, using the crushed vitamin C tablets instead of
emergency vitamin C powder.
9. Record results found.
EXPECTED RESULTS:
Title- Table showing expected results of Vitamin C test
Vitamin C Agents
Trial 1
Trial 2
Trial 3
Vitamin C tablet
Initial value
Final value
Titre
Emergen-C
Initial value
Final value
Titre
TREATMENT OF RESULTS
After the results are collected, find the value that represents the unknown solution.
VARIABLES:
Bibi Assiya Hamid
Chemistry
Unit 1
Lab#
Skill:
Date
● Control- the amount of dissolved vitamin C, distilled water and starch solution used.
● Independent- amount of iodine solution used.
● Dependent- colour change
PRECAUTIONS:
1. Ensure air bubbles are not present in burette.
2. Be careful when handling lab equipment.
3. Avoid skin and eye contact with all chemicals.
TITLE: Identification of cations
AIM: To observe the colour of various metal ions when placed in a flame.
BACKGROUND INFORMATION:
Bibi Assiya Hamid
Chemistry
MATERIALS/ APPARATUS:
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Inert metal loop
Bunsen burner
Potassium
Barium
Calcium
Strontium
Lithium
Sodium
Copper
METHOD:
1.
HGHN
DIAGRAM:
OBSERVATION/ RESULTS:
CALCULATIONS:
Unit 1
Lab#
Skill:
Date
Bibi Assiya Hamid
Chemistry
Unit 1
Lab#
Skill:
DISCUSSION:
PRECAUTIONS:
1.
Ensure air bubbles are not present in pipette
2.
Keep chemical bottles off the bench and do not contaminate pipettes.
SOURCE OF ERROR:
1.
2.
CONCLUSION:
REFERENCES:
TITLE: Heat of Solution
AIM:
Date
Bibi Assiya Hamid
Chemistry
Unit 1
Lab#
Skill:
Date
1. To measure experimentally the amount of heat involved in the dissolving of ammonium
nitrate in water.
2. To relate the heat of solution involved to the two-step process of dissolving.
BACKGROUND INFORMATION:
MATERIALS/ APPARATUS:
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2 Styrofoam cups
thermometer
100 mL graduated cylinder
balance
stirring rod
ammonium nitrate, NH4NO3
METHOD:
1. The mass of a sample of solid ammonium nitrate of approximately 5 grams was found.
2. The mass of a dry pair of Styrofoam cups was found.
3. 50 mL of distilled water was added to the cup and the mass of the cup and water was
found.
4. The water was stirred briefly with a thermometer and the temperature was recorded.
5. The solid was dissolved in the water, stirred with the thermometer and the maximum
temperature difference from the initial reading was recorded.
DIAGRAM:
OBSERVATION/ RESULTS:
Data Tables
Bibi Assiya Hamid
Chemistry
Unit 1
Lab#
Skill:
Date
Ammonium nitrate
Sodium acetate
Mass of empty styrofoam cup =
g
g
Mass of cup and water =
g
g
Mass of NaOH used =
g
g
Initial temperature of H2O =
o
C
o
Final temperature of H2O =
o
o
C
C
C
CALCULATIONS:
1. From your data, calculate the following for each part of the experiment.
a) the temperature change of the water.
b) the mass of water.
c) the quantity of heat absorbed (or given off) by the water during the dissolving.
d) the number of moles of solid used.
e) the quantity of heat involved per mole of solid dissolved. This is called the molar
heat of solution.
Ammonium nitrate
Sodium acetate
Mass of H2O used =
g
g
Formula of solid =
____________
____________
Molecular mass of solid =
g/mol
g/mol
Number of moles of solid =
mol
mol
Temperature change =
o
C
o
Energy released in reaction =
kJ
kJ
Research- What is the accepted value of the heats of solution for the above solid?
Ammonium Nitrate =
_____________________ kJ/mole
The formula weight of NH4NO3 is 80.04g/mol.
C
Bibi Assiya Hamid
Chemistry
Unit 1
Lab#
Skill:
DISCUSSION:
PRECAUTIONS:
1.
Ensure air bubbles are not present in pipette
2.
Keep chemical bottles off the bench and do not contaminate pipettes.
SOURCE OF ERROR:
1.
2.
CONCLUSION:
REFERENCES:
TITLE: Rates of Reaction
AIM:
BACKGROUND INFORMATION:
Date
Bibi Assiya Hamid
Chemistry
MATERIALS/ APPARATUS:
METHOD:
DIAGRAM:
OBSERVATION/ RESULTS:
CALCULATIONS:
DISCUSSION:
Unit 1
Lab#
Skill:
Date
Bibi Assiya Hamid
Chemistry
PRECAUTIONS:
1.
SOURCE OF ERROR:
1.
2.
CONCLUSION:
REFERENCES:
Unit 1
Lab#
Skill:
Date
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