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egg albumen practical

I really reaaly need help on the planning exercise for the denaturation of egg albumen from copper(ii)sulphate,
Any help will be greatly appreciated.
Loz xXx

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Reply 1

Unregistered

Do a practical of the experiment using a range of concentrations of copper sulphate solution(by adding distilled water), adding them to a drop of the albumen in turn and observe how long it takes for the albumen to fully denature,

Hope it helps!!

E-mail me at [email protected] if there's anything else!
Tommie

Reply 2

Unregistered

Lauren this is Dr Donnelly
This is cheating
you're a good student lauren but don't force me to take further action

hehe its not really its claire and harri xxx

LOL

i dont actually think most bio teachers wud class this as cheating......might get mine to come on here.......

Reply 5

Unregistered

Hi all. this egg jobby, we have been pointed in the direction of the colourimeter how about u guys? wot tips have u been given coz i really need some help here. lol. thanx, *Stu*

Reply 6

Unregistered

I think that the calorimetery thingy is the best thing 2 use. Apart from I think it wud b a gud idea to titrate the copper sulphate with the egg albumen. That way u wont hav to make up all of the diffrent concentrations and you will find the exact least number of moles which will be required to denature the fried egg.

Reply 7

Unregistered

o my banana! how does that work exactly?! i can do titrations, but wont the albumen get stuck in the pipettes and burettes cos its so gloopy?! i broke a plastic syringe the other day by trying to suck up a lump of egg white, and nearly killed myself in the process so god help glass ware :s-smilie:

a xXx

Reply 8

Unregistered

hehe

my biology teacher actually told me about this site!!

Reply 9

Unregistered

colorimeters dont work for this one - the precipitate distributes itself unevenly in the solution so a colorimeter can't get an accurate reading

Reply 10

Unregistered

Originally posted by Unregistered
hehe

my biology teacher actually told me about this site!!

whats he calleed ?
mine too

Reply 11

Unregistered

Originally posted by Unregistered
colorimeters dont work for this one - the precipitate distributes itself unevenly in the solution so a colorimeter can't get an accurate reading

Then blend it before putting it in the colorimeter.

Reply 12

Unregistered

U can't blend it coz dat defeats da whole point of trying 2 find how much light gets through da solution. You want to leave the ppt at da bottom so that u can measure light going through the remaining solution (the copper sulphate which hasn't been used up in the reaction with the protein, presuming there is total denaturation). Hope this helps, Sam.

Reply 13

snake_n_shades

mine's called Dr Ford at LRGS

you don't get a nice powdery precipitate when you carry out this experiment, so you can't just wait for the precipitate to settle. I suppose you could filter the remaining solution and calculate the mass of copper sulphate left after the reaction.

honestly its a lot easier to use a qualitative method and just find the concentration of copper sulphate at which a tube full of albumen becomes completely opaque (ie you cant see a shape on a piece of paper behind it)

Reply 14

snake_n_shades

oh and how do you blend about 5ml of solution?

Reply 15

Unregistered

the best thing to do is logarithmic dilution - u start with 0.1 mol dm-3, and you add 1 part copper sulphate solution for 9 parts water. this gives you 0.01. to get to 0.001, add another 10 parts water, 0.0001 another 10 parts etc.

a good tip is to set up a control with distilled water and the albumen, so you can see what the egg albumen should look like when it is not denatured (also gives you bonus marks in the marking scheme)

Reply 16

Unregistered

btw a colouromiter is not such a good idea, and titrations are used for neutralisation reactions, so thats out too.....

Reply 17

Unregistered

Originally posted by Unregistered
I really reaaly need help on the planning exercise for the denaturation of egg albumen from copper(ii)sulphate,
Any help will be greatly appreciated.
Loz xXx

Reply 18

Unregistered

instead of using a colourimeter, could you use a light detector which would then tell you how much light has been absorbed by the precipitate? Then you could find out the % denaturation couldn't you? (Provided that the test tube containing the albumen and copper sulphate has black paper around it)