memorise?

[8039]

What are these ?

Just hormones (kinda) that go around your body giving you pain, aspirin stops them from producing hence less pain. I remember writing an essay about it, but don't remember nothing.

[m@tty]

Probably a good idea to remember that chlorine, carbon, and hydrogen have different isotopes. CL 35 and 37; C-12 and 13; and H-1 and 2(deutrium). Also Bromine 79 and 81. These may be necessary knowledge when having to account for multiple parent ion peaks in mass spec.

[HungTran2009]

CnH2n+1COOH (SFA)

CnH2n-1COOH (MUFA)

CnH2n-3COOH (PUFA)

Goes down by 2 hydrogen atoms each time...I think :/

[chansthename]

Probably a good idea to remember that chlorine, carbon, and hydrogen have different isotopes. CL 35 and 37; C-12 and 13; and H-1 and 2(deutrium). Also Bromine 79 and 81. These may be necessary knowledge when having to account for multiple parent ion peaks in mass spec.

yeah, I have looked into it and 13C is more likely to occur in nature than 2H so that is my preference if I have to decide between 2H and 13C but they should mark both as correct anyway.

[HungTran2009]

Do we have to know gas laws from last year?? (besides PV=nTR)
I've come across a couple questions requiring them in prac exams.

I'm dying right now...btw

[cindyy]

to find the number of double bonds in a polyunsaturated fat, find the saturated number of hydrogens (2n+1) and then minus that from the number of hydrogens in the polyunsaturated fat and divide it by 2.  Thats the number of double bonds! Oh but you leave out the COOH when doing all that!

So for Linolenic acid, the formula is C₁₇H₂₉COOH

A saturated compound would have 17*2 + 1 hydrogens =35

35-29=6
6/2=3

therefore 3 double bonds !!!

[iffets12345]

Hmmm also that symmetrical (i dont like the use of this word...for want of a better one) molecules don't show bands on the IR spectrum like nitrogen and oxygen

[m@tty]

Do we have to know gas laws from last year?? (besides PV=nTR)
I've come across a couple questions requiring them in prac exams.

I'm dying right now...btw

You can derive them.

If mole amount and temperature are constant:



But on the right this is constant

So you can say:

.

Similarly, if pressure and mole are constant:



Again the right is constant so

etc.

Pretty useful.  (Thanks to Mao when XLL was actually running)

[8039]

yield  = actual yield/theoretical yield times a 100

Best thread ever btw!