Assignment 3

24th Feb 2014 is the deadline for assignment 3.

Assignment 3 requires the following pieces of work:

1. report/poster on different separating techniques - how they're carried out and the scientific principles behind them
2. photos/diagrams demonstrating the four we carried out (chromatography, melting point, distillation and filtration)
3. procedure explaining how asprin is made and recrystallised
4. procedure explaining how to carry out the TLC and develop in potassium manganate (VII) solution
5. procedure explaining how to titrate asprin with iron (III) chloride
6. procedure explaining how to titrate asprin with sodium hydroxide
7. procedure explaining how to carry out a melting point of asprin
8. summary of your findings: what was the purity of the asprin, indicated by each method
9. a report describing the factors that influence purity (see assignment brief for more detail)
10. evaluation of three purity checking techniques

You have just under a month (but one whole week of holiday!)

Ms Elias

Extra classes

I blame the cold and flu tablets...

You extra lessons will be Mon P5 Week A (room to be announced, as starting Monday 27th Jan) and Fri P1 Week A (starting 17th Jan - room to be announced).

Sorry for the earlier confusion.

Thanks
Louise

Missing work

I have not received red books from:

Nabeel
Zara
Abed
Hayat
Alan

These need to be handed into me before the weekend. You can leave them with Mrs Robson or you can bring them to W8a (the Tub) and someone will put them in my tray.

I will be in on Friday to collect them.

If I do not see them then your work for task 1 and 2 will be capped at a Pass, as I need evidence of your titration results and the qualitative tests to be able to finish my report on each of you.

Thank you
Ms Elias

Husna, Nirmala and Natalie - I believe I have left your work in my office and do not have it with me at home. If you think you might be in the category above them please hand it in by Friday.

Extra lessons

Hello,

You may have noticed that you have fewer lessons than you are expecting for Medical Science. I have found a way to remedy this.

From Monday 13th Jan (next week) you will have two extra lessons per fortnight.

Mon A P1 in R22
Fri A P1 in W9

These lessons will be taught by Mrs Choudhury. She will be picking up part of the Unit 4 and will start with Task 4.2 and 4.3.

You will be expected to write a summary of the experiment you have carried out in class, including the results and the calculations/conclusions. You will submit this work to me at the final deadline for marking. Mrs Choudhury will write a report on your actions during the practical work, just as I do.

These lessons will appear on your timetable today or tomorrow, and you will therefore be excused from the private study sessions.

If there are any problems with this, and there shouldn't be as I have checked your timetables one by one then you need to email me a.s.a.p.

Thank you
Ms Elias

Cover work 9/01/14

Good morning,

I'm still not well enough to be in work, so I am sorry but you have another cancelled lesson. While I'm away I'm like you to continue working on Task 3 and making some improvements to your tasks you submitted.

You can find a copy of the assignment in the shared area, in case you handed yours in.

I can't give you your feedbacks without giving you your books back, but I can make some generic comments that will apply to all of you:

1. Most of you did not achieve M1 for the titration work. This is because although I had directed you to work on the accuracy material in lesson most of you did not start/complete it to a decent standard. If this is you you need to use your level 3 text books to produce a comprehensive and detailed list of ways to make a titration accurate. Apply it to the titration we carried out - magnesium carbonate in the conical, hydrochloric acid in the burette, phenolphthalein indicator. 
2. I did not give sufficient guidance over D1 and how it applied to the titration work. You need to talk about improvements. Think about all the ways in which accuracy is ensured in a titration and then think about what you did.... how many of you really read at eye level, with a white piece of paper behind? Did you achieve a sensible end point or would it not stay pink? If these problems did occur you need to identify three or four of them and think about the consequences for them.
3. Lots of the M1 work for the qualitative tests is a bit shaky - three lines is not going to get you a merit..... extend what you have written. Look at the criteria again....

Once you've done all of this you should look at what you have submitted for Task 3.1. The methods must have diagrams if the wording is confusing and to fully achieve P2 you have to have explained the science behind your separating technique. For some of you this is clear in the method, for others your method is so brief that it isn't ...

e.g. in filtration you rinse the solid with cold solvent, this removes any impurities that are on the solid because they are soluble in the solvent and the solid isn't. [contains information on the science behind the technique]

Have fun this morning.

There were no IT rooms free to book, so you should take yourself to the library or the sixth form centre.

Thanks
Ms Elias

Cover work 06/01/14

Good morning,

I'm sorry I'm not in today - I still have that ridiculous chest infection. I planned to give your work back to you today, as I cannot do this I will move the deadline by three days.

We were planning to make asprin today and then use TLC to analyse the resulting product. There isn't really any appropriate work for you to undertake apart from preparation:

1. read the procedure (see link below)
2. write out method 1 in your own words, and produce a few diagrams to help it stick in your mind
3. write out the method for using TLC (again, in your own words)

https://drive.google.com/file/d/0BwXkgDfg2V13VW5OZV9GM2RNZkk/edit?usp=sharing

Extension:
research how iron (III) chloride reacts with asprin, and how this chemical can be used to test for the presence of asprin.

If the link doesn't work then please email me!