fatty acids! saturated, unsaturated?

[ltee]

so like, sometimes they give us the formulas for saturated, unsaturated and polyunsaturated fatty acids and they ask us to identify them

 does anyone know the general formulas for them or if there is one?

help me out!!

[ninwa]

so like, sometimes they give us the formulas for saturated, unsaturated and polyunsaturated fatty acids and they ask us to identify them

 does anyone know the general formulas for them or if there is one?

help me out!!

saturated: CnH2n+1COOH

mono-unsaturated: CnH2n-1COOH

poly-unsaturated: CnH2n-3 / 5 / 7 / etcCOOH

.... I think.

[cara.mel]

Nina's right (don't doubt yourself )
Just adding onto it:
If it's written in the form CxHyO2
Saturated: CnH2nO2
Monounsaturated: CnH(2n-2)O2
Polyunsaturated: more then that.

[ninwa]

Nina's right (don't doubt yourself )
Just adding onto it:
If it's written in the form CxHyO2
Saturated: CnH2nO2
Monounsaturated: CnH(2n-2)O2
Polyunsaturated: more then that.

I always doubt myself

I didn't know about that ... did we get taught that? :?

Oh well. When it's written in that form, I just minus one C and one H and keep using my formula regardless

[Collin Li]

Remembering general formulas? Boring!

Just treat the -COOH group as a -H
(e.g: C17H35COOH has the same saturation as C17H36, which is an "alkane," i.e. saturated).

[kingmar]

Theory questions! Crap!

Calculations ftw!

[enwiabe]

Remembering general formulas? Boring!

Just treat the -COOH group as a -H
(e.g: C17H35COOH has the same saturation as C17H36, which is an "alkane," i.e. saturated).

Oh yeah, Coblin. I completely agree. Remembering formulas is annoying! Kind of like remembering the CnH2n+2 formula of alkanes and then applying it to fats.

[cara.mel]

Nina's right (don't doubt yourself )
Just adding onto it:
If it's written in the form CxHyO2
Saturated: CnH2nO2
Monounsaturated: CnH(2n-2)O2
Polyunsaturated: more then that.

I always doubt myself

I didn't know about that ... did we get taught that? :?

Oh well. When it's written in that form, I just minus one C and one H and keep using my formula regardless

I dont think we got taught that, it's one of the things I taught myself when we had to do all the practise exams over the holidays (that she never checked xD) I found they were written that way more often then with the COOH at the end =/
I swear, most of my food chem stuff is just rote learned and I would die having to apply any of it to unfamiliar contexts ^_^

[ninwa]

Oh yeah, Coblin. I completely agree. Remembering formulas is annoying! Kind of like remembering the CnH2n+2 formula of alkanes and then applying it to fats.

Oh snap.  :wink: :roll:


Aww Mel I wish I had your skill for learning-stuff-on-your-own although I love food chem cos it's just unit 3 bio simplified ^^

[sachi_star]

:lol: yay for biol, ot rocks

  boo for chem

[cara.mel]

That's why I hate food chem. Death to all living things, who needs them? =)

Seriously, before we started I barely knew what the difference between proteins, carbohydrates and fats were, and it was the only area of study this unit I've actually studied for in an attempt to learn it, and it seemed like in class only the forumlas were sticking and any worded things (like enzymes, primary/sec/tertiary structure, hell even what the functions of proteins are) were sifting through. On the other hand, I remembered without effort amino acids are zwitterions in water, such a funky name
See, before food chem I wouldn't have known what 'amino acid' means

The only thing I like about it are the carbon/nitrogen cycles o_O

[ninwa]

The only thing I like about it are the carbon/nitrogen cycles o_O

 :?
That's the only bit I hate. Lol =\

[Collin Li]

Oh yeah, Coblin. I completely agree. Remembering formulas is annoying! Kind of like remembering the CnH2n+2 formula of alkanes and then applying it to fats.

Oh snap.  :wink: :roll:

The formula for alkanes is far more accessible than the formula for a saturated fatty acid.

It minimises the amount of memorisation you need, and also keeps you thinking.

[melanie.dee]

fuck fuck i hate rote learning. how am i supposed to learn/memorise all this theory stuff for chem in 2 days?? at the moment, im sweet with equations and calculations, but anything i have to memorise is SHOCKING. food chem, nitrogen/carbon cycles. ahhhhhhhhhhhhh how am i going to memorise it all! i dearly hope the exam is most calculations

[Ahmad]

That's exactly how I feel mel. You are not alone.

Physics has barely any content. But chemistry's a monster!  :shock: