Essay
Unit 4 - M1 explain how accuracy may be ensured in the techniques used
- Institution
- PEARSON (PEARSON)
This is my M1 task for my distinction graded unit 4 assignment
[Show more]
Content preview
Unit 4 – scientific practical techniquesM1 – Explain how accuracy may be ensured in the techniques used
For the quantitative and qualitative tests carried out, accurate techniques were necessary as without
them, incorrect results would have been obtained. In each test carried out special equipment was
used as it enabled not only the techniques to be smooth and precise but also allowed the results to
be as close to accurate as possible.
In the qualitative test for starch, a spotting tile was used over test tubes for two reasons. One being
that the spotting tiles white base meant that any colour change could visually be seen against the
white background where as a test tube is clear and so human error could have been made. The
second reason being that all the different foods being tested could fit onto one spotting tile instead
of using 9 different test tubes. This meant less washing up was needed to be done but also meant
that the experiment was relatively safer as no glass was available to be broken.
In the qualitative test for lipids not only was the test tube shaken instead of waiting for fat droplets
to occur, but filter paper was used for solid foods. This overall meant less test tubes were being used
and regarding solid foods, a more accurate result was given. However, errors that occurred or could
occur with the use of spotting tiles is contamination. Due to the wells being so shallow, when
dropping each piece of food into their own well, for example the Tropicana juice, this food could
have easily splashed into another well causing contamination of that piece of food and possibly
giving incorrect results. Another way contamination could have occurred is by people getting mixed
up with the pipettes. Pipettes should only be used for one type of food as if one type of food was
picked up and then another, then the second piece of food and other pieces thereafter will be
contaminated with the ones before it automatically causing negative results.
In the qualitative test for cations we held the nichrome wire in the flame before testing each
unknown compound. This is because by doing this we are removing any particles the wire might
picked up from being placed on surfaces. If this wasn’t carried out each time, then the nichrome
wire could give off a different colour than expected and incorrect results would have been received.
…………………………………………………………………………………………………………………………………………………….
Thank you for previewing the example, feel free to buy the singular task, or the Unit 4 bundle xxx
The benefits of buying summaries with Stuvia:
Guaranteed quality through customer reviews
Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.
Quick and easy check-out
You can quickly pay through credit card for the summaries. There is no membership needed.
Focus on what matters
Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!
Frequently asked questions
What do I get when I buy this document?
You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.
Satisfaction guarantee: how does it work?
Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.
Who am I buying these notes from?
Stuvia is a marketplace, so you are not buying this document from us, but from seller kacieleax. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for £2.99. You're not tied to anything after your purchase.
Can Stuvia be trusted?
4.6 stars on Google & Trustpilot (+1000 reviews)
60281 documents were sold in the last 30 days
Founded in 2010, the go-to place to buy revision notes and other study material for 14 years now