BTEC UNIT 2A
TITRATION
ASSESSMENT
,BTEC NQF National Diploma in Applied Science.
Learner name:
Unit title: Unit 2A: Practical Scientific Procedures and
Techniques.
Learning aim: A: Undertake titration and colorimetry to
determine the concentration of solutions.
Assignment title: Keeping up the standards.
Introduction
1|Page
, The assessment required me to find the concentration of an unknown hydrochloric acid, I will prepare
a standard solution of Na2CO3 and titrate this against an HCl solution of unknown concentration.
This was accomplished by having to first find the concentration of the hydrochloric acid (HCL), by using
titrating the HCL with the standard solution of sodium carbonate (Na2CO3).
Making the standard solution of sodium carbonate / Calibration of Balance
The first thing was to prepare the sodium carbonate standard solution. In order to measure the
sodium carbonate, we had to calibrate the balance, this was accomplished by using a mass that was
exactly 200g. From this we can determine the weight from the actual 200g, for example if the balance
read 200.3g, then you would +0.3g from the final measurement you get when measuring the
substance, if the balance read 198.5g then you would -1.5g from the final outcome. This is a very
crucial point in this investigation as it would affect the results and we wouldn’t get accurate results.
To make sodium carbonate solution, the measurements have to be precise. So in order to be sure that
we get accurate results, we ensured that we rinsed and cleaned all the equipment to prevent
contamination. The equipment was also dried to avoid the sodium
carbonate from sticking to the side of the beaker in case some was to be
removed due to being over the desired weight. In order to actually make
the solution, we had to mix the measured sodium carbonate with 250ml
of distilled water. This was done by adding the distilled water bit by bit to
prevent going over the desired limit, the volumetric flask was marked at
the 250ml point, this made it easier to read the measurement and get
accurate results. The distilled water was added with a washing bottle to
make sure that the water added as slowly as possible to avoid the water
to overflow, if the water was to overflow then the mixture would not have
been fair as it would contain more water then sodium carbonate.
Calibration of the balance
On the balance a watch glass was placed so we there would be somewhere the sodium carbonate
would stay, and could easily be transferred from one place to another. Before adding the sodium
carbonate, the scale was zeroed to prevent any altercations between the measurements. The scale
that we calibrated came to a 200.2g, this means that we had to +0.2g from the final measurement in
order to get the exact number. We added 10.6g to the weighing boat using a spatula, the 0.2g was
added at the end of the measurement.
The solution was first poured into a beaker to make it so we can the sodium carbonate bit by bit to
avoid getting any clumps, I heated the beaker to allow the solution to dissolve at a faster rate. This
was accomplished by using a Bunsen burner, this would make the particles move much faster allowing
them to dissolve quicker, the mixture was stirred with a glass rod with a flat end to help with the
process. The solution was then placed in a volumetric flask to make sure that the solution was mixed
thoroughly and there would be no lumps of sodium carbonate. To mix this I had to make sure that I
turned the flask over and started to shake the top in a circular motion, the flask was then
2|Page
TITRATION
ASSESSMENT
,BTEC NQF National Diploma in Applied Science.
Learner name:
Unit title: Unit 2A: Practical Scientific Procedures and
Techniques.
Learning aim: A: Undertake titration and colorimetry to
determine the concentration of solutions.
Assignment title: Keeping up the standards.
Introduction
1|Page
, The assessment required me to find the concentration of an unknown hydrochloric acid, I will prepare
a standard solution of Na2CO3 and titrate this against an HCl solution of unknown concentration.
This was accomplished by having to first find the concentration of the hydrochloric acid (HCL), by using
titrating the HCL with the standard solution of sodium carbonate (Na2CO3).
Making the standard solution of sodium carbonate / Calibration of Balance
The first thing was to prepare the sodium carbonate standard solution. In order to measure the
sodium carbonate, we had to calibrate the balance, this was accomplished by using a mass that was
exactly 200g. From this we can determine the weight from the actual 200g, for example if the balance
read 200.3g, then you would +0.3g from the final measurement you get when measuring the
substance, if the balance read 198.5g then you would -1.5g from the final outcome. This is a very
crucial point in this investigation as it would affect the results and we wouldn’t get accurate results.
To make sodium carbonate solution, the measurements have to be precise. So in order to be sure that
we get accurate results, we ensured that we rinsed and cleaned all the equipment to prevent
contamination. The equipment was also dried to avoid the sodium
carbonate from sticking to the side of the beaker in case some was to be
removed due to being over the desired weight. In order to actually make
the solution, we had to mix the measured sodium carbonate with 250ml
of distilled water. This was done by adding the distilled water bit by bit to
prevent going over the desired limit, the volumetric flask was marked at
the 250ml point, this made it easier to read the measurement and get
accurate results. The distilled water was added with a washing bottle to
make sure that the water added as slowly as possible to avoid the water
to overflow, if the water was to overflow then the mixture would not have
been fair as it would contain more water then sodium carbonate.
Calibration of the balance
On the balance a watch glass was placed so we there would be somewhere the sodium carbonate
would stay, and could easily be transferred from one place to another. Before adding the sodium
carbonate, the scale was zeroed to prevent any altercations between the measurements. The scale
that we calibrated came to a 200.2g, this means that we had to +0.2g from the final measurement in
order to get the exact number. We added 10.6g to the weighing boat using a spatula, the 0.2g was
added at the end of the measurement.
The solution was first poured into a beaker to make it so we can the sodium carbonate bit by bit to
avoid getting any clumps, I heated the beaker to allow the solution to dissolve at a faster rate. This
was accomplished by using a Bunsen burner, this would make the particles move much faster allowing
them to dissolve quicker, the mixture was stirred with a glass rod with a flat end to help with the
process. The solution was then placed in a volumetric flask to make sure that the solution was mixed
thoroughly and there would be no lumps of sodium carbonate. To mix this I had to make sure that I
turned the flask over and started to shake the top in a circular motion, the flask was then
2|Page
