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Re-studying Chemistry after a 6 year hiatus

After leaving school 6 years ago with a B in GCSE in Chemistry, I want to study it at A Level after dropping out of college now that I've decided to want to pursue a degree in Physics and Astronomy.

After not studying any Chemistry whatsoever for 6 years my knowledge has dried up a bit, so what is the best way to refresh my knowledge back to a level at which I would have been going to college with, without retaking an entire GCSE?
Original post by BradPennick
After leaving school 6 years ago with a B in GCSE in Chemistry, I want to study it at A Level after dropping out of college now that I've decided to want to pursue a degree in Physics and Astronomy.

After not studying any Chemistry whatsoever for 6 years my knowledge has dried up a bit, so what is the best way to refresh my knowledge back to a level at which I would have been going to college with, without retaking an entire GCSE?


Read
Reply 2
Original post by charco
Read


Thank you so much for that incredibly helpful advice.
Original post by BradPennick
Thank you so much for that incredibly helpful advice.


Books, I mean.
Reply 4
Original post by charco
Books, I mean.


Oh that changes things! I thought I was meant to read the ingredients of dishwasher tablets!
Reply 5
Original post by BradPennick
Oh that changes things! I thought I was meant to read the ingredients of dishwasher tablets!


Watch videos on khan academy, or view notes that you can find online.
Reply 6
Original post by azefayuu
Watch videos on khan academy, or view notes that you can find online.


Thanks for an actual suggestion. I'll have a look at some of their stuff :smile:
Original post by BradPennick
Thanks for an actual suggestion. I'll have a look at some of their stuff :smile:


Steps for Success:

1) Download the specification for A-level Chemistry for your board.
2) Subscribe to "Tyler Dewitt" and Khan Academy on Youtube.
3) Buy one large notepad and one smaller notepad. The larger notepad is for your notes and the smaller notepad is for your definitions & formulae.
4) Actively use the website A-levelchemistry.co.uk - They have fantastic resources AND lots of questions (homework exercises and tests which are great for practise!) Also use chemrevise which has lots of great notes! :smile:
5) Past papers all day, every day.
6) Develop a love for the beauty that is Chemistry. It's the central science after all. Chemistry is the study of matter which goes from fields such as Quantum Mechanics to how the origin of life. It's beauty and truth!

- HS!
(edited 8 years ago)
Actually not a bad place to start ...

"Dishwasher tablets and powders contain a surprising mix of chemicals, far more than just the detergent you might expect.

These are as follows:

Surfactants (detergents) - these promote mixing between oil- and fat-based soil and water.
Alkalis - these emulsify grease and adjust the pH of the water to the optimum for the other components to work
Bleaches - these oxidise coloured substances to colourless ones
Biosubstances - these are enzymes that break down starch- and protein-based soils
Builders - these help to soften water and trap metal ions that would interfere with the cleaning process and hold dirt in solution
Auxiliaries - these include substances used to make and disintegrate the tablet as well as colours and perfumes

One problem that may be encountered is getting all these different ingredients to work together when they have different optimum conditions. Enzymes, for example, work best at moderate temperatures around 50 °C . They are denatured and will no longer work if they have been exposed to temperatures much above this for any length of time.

On the other hand, grease removal will work best at high temperatures when fats melt to oils making them easier to remove. And, of course, all chemical reactions go faster at higher temperatures - twice as fast for every 10 °C rise is a useful rule of thumb.

There is a similar issue with pH. Cleaning takes place best at alkaline pHs but the optimum pH for most enzymes is neutral to mildly alkaline - they are denatured in strongly acidic or alkaline environments. The optimum pH for the bleach, however, is around 10."

Get your head around that - there's loads of chemistry involved.

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