Criteria covered by this task:
Unit/Criteria
To achieve the criteria you must show that you are able to:
reference
Evaluate the accuracy of procedures and techniques used in
A.D1 Y titration and colorimetry in relation to outcomes and suggest
improvements.
Demonstrate skilful application of procedures and techniques in
A.M1 Y titration and colorimetry to accurately determine the
concentration of solutions.
Correctly prepare and standardise solutions for titration and
A.P1 Y
colorimetry.
Investigate the concentration of unknown solutions, using procedures
A.P2 Y
and techniques in titration and colorimetry.
Unit 2A
Preparation of primary standard solution
A balance must be calibrated to guarantee that it is producing precise and
accurate data. The balance's readings are compared to a known standard
weight as part of the calibration process.
The stages to calibrating a balance are as follows:
1. Make sure the balance is spotless and devoid of any materials or debris
that could tamper with the measurement's accuracy.
2. Set the balance with a well-known standard weight which is a weighing
boat. The weight must be clean and free of any debris, and it must be
suitable for the balance's range.
3. Take note of the weight that appears on the balance and contrast it with
the standard weight's known weight. If there is a substantial discrepancy
between the two, change the balance until the readings match
4. To make sure the balance is precise across the whole weighing range,
repeat the operation using several standard weights at various locations.
5. Keep track of the calibration process results and any balance
modifications.
6. To guarantee that the balance stays precise over time, check and
recalibrate it frequently.
A.P1
1 2 3
Reading on 200.068g 200.060g 200.058g
balance (g)
, 1. Transfer the weighed sodium carbonate into a clean beaker after
weighing the weighing boat and the mass of the solids.
2. Reweigh the weighing boat
3. To fully dissolve the solute, add 100cm3 of distilled water to the beaker
and stir with a glass stirring rod.
4. Pour the beaker's contents into a volumetric flask using a funnel.
5. To add the leftover solution to the flask, rinse the stirring rod into the
beaker.
6. Just 2 cm3 of the volumetric flask should be raised above the calibration
mark.
7. Add extra distilled water to the beaker at eye level, mix it, then carefully
pour in the final few cm3 to raise the solution to the meniscus mark.
8. Last, shake the contents of the volumetric flask after covering it.
Table of results A.P1
TABLE OF MASS OF WEIGHING BOAT BEFORE/AFTER/WITH Na2CO3
Initial Weighing boat mass (g) 2.4619
Weighing boat + Na2CO3 (g) 3.769
Mass of weighing dish after transfer 2.476
of Na2CO3 (g)
Mass of Na2CO3 (g) 1.293
Calculations
1) Finding the molar mass of Na2CO3:
(2 x the atomic mass of Na+ The atomic mass of C+ (3 x the atomic mass of O))
=
(2 x 22.99g mol-1 + 12.01mol-1 + (3 x 16.00)g mol-1 ) = 105.99g mol-1
Molar mass of Na2CO3 is 105.99g mol-1
2) Find the Moles of Na2CO3
Moles = Molar mass/mass = 1.293/105.99mol -1 = 0.0121mol
3) Calculating the concentration of Na2CO3
Conc = vol/mol = 0.0121/0.25 = 0.0484 mol dm-3 (3dp) A.P1
Unit/Criteria
To achieve the criteria you must show that you are able to:
reference
Evaluate the accuracy of procedures and techniques used in
A.D1 Y titration and colorimetry in relation to outcomes and suggest
improvements.
Demonstrate skilful application of procedures and techniques in
A.M1 Y titration and colorimetry to accurately determine the
concentration of solutions.
Correctly prepare and standardise solutions for titration and
A.P1 Y
colorimetry.
Investigate the concentration of unknown solutions, using procedures
A.P2 Y
and techniques in titration and colorimetry.
Unit 2A
Preparation of primary standard solution
A balance must be calibrated to guarantee that it is producing precise and
accurate data. The balance's readings are compared to a known standard
weight as part of the calibration process.
The stages to calibrating a balance are as follows:
1. Make sure the balance is spotless and devoid of any materials or debris
that could tamper with the measurement's accuracy.
2. Set the balance with a well-known standard weight which is a weighing
boat. The weight must be clean and free of any debris, and it must be
suitable for the balance's range.
3. Take note of the weight that appears on the balance and contrast it with
the standard weight's known weight. If there is a substantial discrepancy
between the two, change the balance until the readings match
4. To make sure the balance is precise across the whole weighing range,
repeat the operation using several standard weights at various locations.
5. Keep track of the calibration process results and any balance
modifications.
6. To guarantee that the balance stays precise over time, check and
recalibrate it frequently.
A.P1
1 2 3
Reading on 200.068g 200.060g 200.058g
balance (g)
, 1. Transfer the weighed sodium carbonate into a clean beaker after
weighing the weighing boat and the mass of the solids.
2. Reweigh the weighing boat
3. To fully dissolve the solute, add 100cm3 of distilled water to the beaker
and stir with a glass stirring rod.
4. Pour the beaker's contents into a volumetric flask using a funnel.
5. To add the leftover solution to the flask, rinse the stirring rod into the
beaker.
6. Just 2 cm3 of the volumetric flask should be raised above the calibration
mark.
7. Add extra distilled water to the beaker at eye level, mix it, then carefully
pour in the final few cm3 to raise the solution to the meniscus mark.
8. Last, shake the contents of the volumetric flask after covering it.
Table of results A.P1
TABLE OF MASS OF WEIGHING BOAT BEFORE/AFTER/WITH Na2CO3
Initial Weighing boat mass (g) 2.4619
Weighing boat + Na2CO3 (g) 3.769
Mass of weighing dish after transfer 2.476
of Na2CO3 (g)
Mass of Na2CO3 (g) 1.293
Calculations
1) Finding the molar mass of Na2CO3:
(2 x the atomic mass of Na+ The atomic mass of C+ (3 x the atomic mass of O))
=
(2 x 22.99g mol-1 + 12.01mol-1 + (3 x 16.00)g mol-1 ) = 105.99g mol-1
Molar mass of Na2CO3 is 105.99g mol-1
2) Find the Moles of Na2CO3
Moles = Molar mass/mass = 1.293/105.99mol -1 = 0.0121mol
3) Calculating the concentration of Na2CO3
Conc = vol/mol = 0.0121/0.25 = 0.0484 mol dm-3 (3dp) A.P1
