06/11BTEC Assignment Brief
Qualification Pearson BTEC Level 3 National Extended Diploma in Applied Science
Unit number and title
Unit 2: Practical Scientific Procedures and Techniques
A: Undertake titration and colorimetry to determine the
Learning aim(s) (For NQF only) concentration of solutions.
Concentrate on keeping up your standards
Assignment title
Assessor
Issue date
Hand in deadline
You are a newly appointed technical assistant at a large chemical
Company , Chemscale.
You have been given the role of testing chemscales testing facilities.
Vocational Scenario or You have been asked to develop methods for Titration and
Context colorimetry . As part of your task you will need to produce repeat
results to confirm robustness. Standardisation of all techniques
needs to take place. A report will need to be written to confirm your
findings.
Task 1 Evaluate the accuracy and safety of the following quantitative
procedures and techniques in relation to their outcomes.
Your practical work must be undertaken correctly and safely at all
times.
Your techniques will need to be performed to a high degree of
accuracy and precision in order to obtain reliable and valid
outcomes.
You will be observed performing your preparation of solutions,
calibration of equipment and application of titration and
colorimetry techniques.
Titration:
, You will perform different titrations to accurately and skilfully
determine the concentration of a solution of sodium hydroxide.
You will first need to calibrate the equipment that you will use
for these titrations which will include: the pipette, the weighing
balance and the pH meter (using buffer solutions).
Your practical work will involve three stages:
o Preparation of a primary standard solution of Na 2CO3 by
weighing the solid, using the calibrated weighing balance,
mixing and dissolving in water, and making up the solution
to an accurate volume
o Accurate standardisation of a given concentration of
hydrochloric acid (HCl) by titration with your primary
standard solution of Na2CO3 and using the calibrated
pipette
o Titration of the sodium hydroxide (NaOH) solution of
unknown concentration with the standardised HCl
You must use two different titration techniques in your
determination of the concentration of sodium hydroxide
(NaOH):
o by use of an appropriate indicator to determine the
end point
o by use of the calibrated pH meter to monitor the pH
change before, during and after the end point
You must produce accurate, precise and reliable results
from both techniques
You must calculate the concentration of NaOH solution:
o directly from your recorded results, in the titration
technique using the indicator
o by plotting and using a graph of pH against volume
of HCl, in the titration technique using the pH meter
Colorimetry:
You will use a colorimeter (or visible spectrometer) to
accurately and skilfully determine the concentrations of Sample
A and B, which are two different concentrations of copper(II)
sulfate (CuSO4) solution that you will be provided with.
Your practical work will involve:
o Preparing your own known concentration of CuSO 4
solution by weighing hydrated copper(II) sulfate solid
(CuSO4.5H2O), dissolving in water and making up to an
accurate volume
o Accurately dilute your stock CuSO4 solution to produce a
series of CuSO4 standard solutions of different
concentrations
o Select an appropriate filter / wavelength for the
colorimeter or visible spectrometer that you will use to
measure the absorbance (or transmission) of the CuSO 4
solutions
o Calibrate the colorimeter / visible spectrometer according
, to the manufacturer’s instructions or practical instructions
provided
o Measure and record the absorbance (or transmission) for
each of your CuSO4 solutions
o Plot a calibration curve of absorbance (or transmission)
against concentration of CuSO4
o Measure and record the absorbance (or transmission) for
Sample A and B (unknown concentrations of CuSO 4
solution) that you are provided with
o Use the calibration curve to determine the concentrations
of Sample A and B
You must produce accurate, precise and reliable results
from your colorimetry technique
Report:
Produce a report of your practical work, which will:
Provide an account of the experiments, including all
observations, measurements, tables of results, calculations and
graphs
Evaluate the accuracy of your results, providing sound
justification and reasoning, and comparing the concentrations
you have determined with actual (or published) concentrations
and with those of other learners
Explain how accuracy, precision and reliability were ensured
during your experiments, and discuss any problems or issues
that occurred during performance of the experiments
Propose improvements or alternatives to the procedures and
techniques, providing a strong rationale why they will improve
accuracy, precision, reliability or validity
Discuss the hazards and risks associated with the procedures
and techniques you have used, justifying the way in which
certain procedures were carried out in a particular way on
grounds of safety
Checklist of evidence A report on the use of Na2CO3 to standardise HCl and
required how HCl is then used to determine the concentration of
NaOH solution by titration, including results (and graph)
from indicator and pH meter methods
A report on the determination of the concentration of
copper(II) sulfate solutions by use of colorimetry, to
include results, calculations and calibration graph
The reports must also include your results from checking
the calibration of the pipette, balance(s) and pH meter
for titration and for the equipment used for colorimetry
Evaluation of the accuracy of the procedures and
techniques, suggested improvements and discussion of
safety aspects
Qualification Pearson BTEC Level 3 National Extended Diploma in Applied Science
Unit number and title
Unit 2: Practical Scientific Procedures and Techniques
A: Undertake titration and colorimetry to determine the
Learning aim(s) (For NQF only) concentration of solutions.
Concentrate on keeping up your standards
Assignment title
Assessor
Issue date
Hand in deadline
You are a newly appointed technical assistant at a large chemical
Company , Chemscale.
You have been given the role of testing chemscales testing facilities.
Vocational Scenario or You have been asked to develop methods for Titration and
Context colorimetry . As part of your task you will need to produce repeat
results to confirm robustness. Standardisation of all techniques
needs to take place. A report will need to be written to confirm your
findings.
Task 1 Evaluate the accuracy and safety of the following quantitative
procedures and techniques in relation to their outcomes.
Your practical work must be undertaken correctly and safely at all
times.
Your techniques will need to be performed to a high degree of
accuracy and precision in order to obtain reliable and valid
outcomes.
You will be observed performing your preparation of solutions,
calibration of equipment and application of titration and
colorimetry techniques.
Titration:
, You will perform different titrations to accurately and skilfully
determine the concentration of a solution of sodium hydroxide.
You will first need to calibrate the equipment that you will use
for these titrations which will include: the pipette, the weighing
balance and the pH meter (using buffer solutions).
Your practical work will involve three stages:
o Preparation of a primary standard solution of Na 2CO3 by
weighing the solid, using the calibrated weighing balance,
mixing and dissolving in water, and making up the solution
to an accurate volume
o Accurate standardisation of a given concentration of
hydrochloric acid (HCl) by titration with your primary
standard solution of Na2CO3 and using the calibrated
pipette
o Titration of the sodium hydroxide (NaOH) solution of
unknown concentration with the standardised HCl
You must use two different titration techniques in your
determination of the concentration of sodium hydroxide
(NaOH):
o by use of an appropriate indicator to determine the
end point
o by use of the calibrated pH meter to monitor the pH
change before, during and after the end point
You must produce accurate, precise and reliable results
from both techniques
You must calculate the concentration of NaOH solution:
o directly from your recorded results, in the titration
technique using the indicator
o by plotting and using a graph of pH against volume
of HCl, in the titration technique using the pH meter
Colorimetry:
You will use a colorimeter (or visible spectrometer) to
accurately and skilfully determine the concentrations of Sample
A and B, which are two different concentrations of copper(II)
sulfate (CuSO4) solution that you will be provided with.
Your practical work will involve:
o Preparing your own known concentration of CuSO 4
solution by weighing hydrated copper(II) sulfate solid
(CuSO4.5H2O), dissolving in water and making up to an
accurate volume
o Accurately dilute your stock CuSO4 solution to produce a
series of CuSO4 standard solutions of different
concentrations
o Select an appropriate filter / wavelength for the
colorimeter or visible spectrometer that you will use to
measure the absorbance (or transmission) of the CuSO 4
solutions
o Calibrate the colorimeter / visible spectrometer according
, to the manufacturer’s instructions or practical instructions
provided
o Measure and record the absorbance (or transmission) for
each of your CuSO4 solutions
o Plot a calibration curve of absorbance (or transmission)
against concentration of CuSO4
o Measure and record the absorbance (or transmission) for
Sample A and B (unknown concentrations of CuSO 4
solution) that you are provided with
o Use the calibration curve to determine the concentrations
of Sample A and B
You must produce accurate, precise and reliable results
from your colorimetry technique
Report:
Produce a report of your practical work, which will:
Provide an account of the experiments, including all
observations, measurements, tables of results, calculations and
graphs
Evaluate the accuracy of your results, providing sound
justification and reasoning, and comparing the concentrations
you have determined with actual (or published) concentrations
and with those of other learners
Explain how accuracy, precision and reliability were ensured
during your experiments, and discuss any problems or issues
that occurred during performance of the experiments
Propose improvements or alternatives to the procedures and
techniques, providing a strong rationale why they will improve
accuracy, precision, reliability or validity
Discuss the hazards and risks associated with the procedures
and techniques you have used, justifying the way in which
certain procedures were carried out in a particular way on
grounds of safety
Checklist of evidence A report on the use of Na2CO3 to standardise HCl and
required how HCl is then used to determine the concentration of
NaOH solution by titration, including results (and graph)
from indicator and pH meter methods
A report on the determination of the concentration of
copper(II) sulfate solutions by use of colorimetry, to
include results, calculations and calibration graph
The reports must also include your results from checking
the calibration of the pipette, balance(s) and pH meter
for titration and for the equipment used for colorimetry
Evaluation of the accuracy of the procedures and
techniques, suggested improvements and discussion of
safety aspects
