Author Topic: Lactic acid  (Read 6182 times)

holtadit

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Lactic acid
« on: November 06, 2009, 11:00:50 am »
Look at question B9)D)ii

What is the displayed structural formula ??

you will find bothe the question paper and markscheme attached

Offline @d!_†oX!©

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Re: Lactic acid
« Reply #1 on: November 06, 2009, 11:10:21 am »
this is what the product will look like
here the C2H5OH will replace Hydrogen from the third carbon...
The H removed will react with the OH from ethanol to form water and this new compound will be formed
AAL IZZ WELL!!! ;)

holtadit

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Re: Lactic acid
« Reply #2 on: November 06, 2009, 11:20:04 am »
Could u give me the displayed structural formula too - for my reference

nid404

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Re: Lactic acid
« Reply #3 on: November 06, 2009, 11:20:44 am »
basically for any esterification....remember water is lost. Oh from ethanol is used....and one H from the acid is used to form water......

Put the rest of the structure as it is.....acid followed by alcohol......but while naming remember u name the alkyl(formed from alcohol) first and then the acid+oate

I'm dead tired...so im bound to say crap in this state....if u spot summin wrong lemme know.....

nid404

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Re: Lactic acid
« Reply #4 on: November 06, 2009, 11:22:20 am »
Could u give me the displayed structural formula too - for my reference

wait u want the structural formula or the displayed formula....2 different things actually.......what he's uploaded is a partially displayed formula i would say

nid404

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Re: Lactic acid
« Reply #5 on: November 06, 2009, 11:27:40 am »
lactic acid structural formula is CH3CHOHCOOH
ethanol is CH3CH2OH


so structural formula of ethyl lactate would be...CH3CHOHCOOCH2CH3
« Last Edit: November 06, 2009, 11:30:53 am by nid404 »

Offline @d!_†oX!©

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Re: Lactic acid
« Reply #6 on: November 06, 2009, 11:31:55 am »
perhaps this is wat u wanted
AAL IZZ WELL!!! ;)

nid404

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Re: Lactic acid
« Reply #7 on: November 06, 2009, 11:32:55 am »
perhaps this is wat u wanted

this is displayed formula

the one I gave above is structural....so uve got both now

Offline @d!_†oX!©

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Re: Lactic acid
« Reply #8 on: November 06, 2009, 11:34:50 am »
i already gave the structural formula nid...bt still thanks... ;D
AAL IZZ WELL!!! ;)

holtadit

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Re: Lactic acid
« Reply #9 on: November 06, 2009, 11:35:47 am »
Thanks ppl understood everything now !!

Offline @d!_†oX!©

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Re: Lactic acid
« Reply #10 on: November 06, 2009, 11:36:46 am »
yr welcome ari....
keepp posting question like these....really interested in chem nd like solving especially ur question... :)
AAL IZZ WELL!!! ;)

nid404

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Re: Lactic acid
« Reply #11 on: November 06, 2009, 11:38:42 am »
i already gave the structural formula nid...bt still thanks... ;D

we ll the one u gave is actually not structural....structural formula shows the arrangement like specifically.....so u can't give the diagrammatic representation......and even if u write it like this with the bonds....u will have to show each bond separately like.....u can't put the last part as C2H5.....it has to be CH2CH3....very specific

Offline @d!_†oX!©

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Re: Lactic acid
« Reply #12 on: November 06, 2009, 11:44:47 am »
kk...thanks nid....
AAL IZZ WELL!!! ;)

Offline Ghost Of Highbury

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Re: Lactic acid
« Reply #13 on: November 06, 2009, 03:55:10 pm »
basically for any esterification....remember water is lost. Oh from ethanol is used....and one H from the acid is used to form water......

Put the rest of the structure as it is.....acid followed by alcohol......but while naming remember u name the alkyl(formed from alcohol) first and then the acid+oate

I'm dead tired...so im bound to say crap in this state....if u spot summin wrong lemme know.....

OH from the acid (lactic) is used, not ehanol. (alchol)
divine intervention!

nid404

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Re: Lactic acid
« Reply #14 on: November 06, 2009, 04:16:14 pm »
I think I'm write abt this......OH from ethanol used....and H from acid.....

hence the formula of ester still has a double oxygen with the acid......this can be further confirmed as the ester is alkyl( which confirms there is no OH) + acid...+ate