BTEC Level 3 Applied/Forensic Science
Unit 2: Practical Scientific Procedures and Techniques
Learning Aim D: Review personal development of scientific skills for laboratory work.
Review of personal development of scientific skills for laboratory work
During year one I developed and learnt a number of skills and techniques in practical
investigations, in order to effectively complete Unit 2. Many were skills I had learnt during my
GCSE Science courses, and I was able to further refine and practise these skills. Others
were new and more advanced (Level 3). I have learnt new things and done new things I had
never done before and learnt techniques which have given me more confidence and
independence in my laboratory work. When applying for a job in the science industry they
will be looking for someone who shows investigative and hands-on ability, and I feel like I
have made good progress in building these skills.
During unit 2 I explored titrations, colorimetry, chromatography, and calorimetry techniques
which required me to work independently and with others in practical lab skills. When looking
back over the course I have reflected on the skills that I have developed and looked over my
proficiency in using equipment and techniques. The skills gained from this unit will be carried
forward to the other units and will help me successfully complete them.
I have made a table to help show how my skills have developed over the time of this course:
Skills I had when starting Skills I gained during unit 2 Skills to develop further
the course
Using a pipette to drop liquids Using a micropipette to To use a Multichannel Pipette
transfer measured amounts of
liquid
Work under supervision and Work independently with Work fully independently
support of a teacher small guidance confidently
Knowing the basic safety and Use a range of PPE correctly Understand the safety and
use of PPE (Personal emergency procedures when
Protective Equipment) using hazardous materials
Measuring the temperature Using a digital and liquid Learn to use infrared
using a liquid thermometer thermometer and comparing thermometers
them
Knowing the different pH and Carry out titrations using a pH Carry out titrations using
their colours meter more than 1 type of probe
Only carried out paper Carried out TLC and paper Carry out TLC and paper
chromatography in a group chromatography in a group chromatography
, with teacher supervision independently and confidently
with no supervision
Dissolving solids Dissolving exact amounts to Build a standard curve using
make a standard solution serial dilutions
Using different equipment and Calibrating equipment in pairs Calibrating equipment
weighing to the gram, e.g., independently and precisely
scales
Where I put in the table above where it says ‘skills to develop further’ some of them are
possible to reach within the next year at school, however with only limited resources and
equipment at school I may need to do outside of schoolwork and experience to gain these
scientific skills, like work experience for example.
Chromatography
Before starting the assignment, I had only carried out paper chromatography. However, in
order to complete the unit, I had to learn new techniques to carry out thin layer
chromatography (TLC) successfully. My group and many others in my class didn’t realise
how important it was to not touch the surface of the TLC plate as it can get sweat, dirt and oil
from your hands on it which can contaminate and affect the results.
As well as this, when placing the chromatography paper into the solvent in the fume
cupboard we had to make sure that the paper wasn’t too low and that the solvent was just
below the pencil line drawn, as if it was above the line then the sample would be dissolved
into the solvent and the results would be inaccurate.
This meant that following instructions and working together was important for this
practical. I think my techniques and skills during the practical could be improved by repeating
the experiment again 2 or 3 more times to make the results more reliable (accurate) and
practise my skills to see where I need to improve. I did compare my results with the results
gained by other groups, in order to check for anomalous results and to ensure that our
results were similar to theirs. If there was a difference in these results, we would have had to
re-do the experiment (thankfully this never happened).
Another skill I developed was the use of different pipettes. Before the start of this
unit, I had only used transfer pipettes in past science lessons, however now I am confident in
using micropipettes, volumetric pipettes, and capillary pipettes. This means I can now find
results with much more accuracy (because the equipment has a higher resolution). I want to
extend my skills further by learning how to use a Multichannel Pipette, these are used in
industrial laboratories in forensic science. A multichannel pipette takes more than one tip at
a time, saves a time and is precise (allows for high levels of precision because each channel
is identical). It looks fun and interesting to use.
When carrying out chromatography my teacher pointed out that I made a few
mistakes when using the micropipette: I put too much liquid onto the chromatography paper,
making the dot too big which took longer to dry. However, after some practise I my technique
improved, and I was able to place the correct amount on the paper.
Titrations
From carrying out titrations I am now confident in performing calibrations, measuring from
the bottom of the meniscus, and using a range of pipettes.
Permanent skills developed.
Some techniques I have learnt during this unit have become automatic after repeating them
over and over. For example, making sure the funnel at the top of the burette is removed and
that the tap needs to be off before filling it up. As well as this making sure to read the
