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VCE Stuff => VCE Science => VCE Mathematics/Science/Technology => VCE Subjects + Help => VCE Chemistry => Topic started by: mandy on February 07, 2010, 05:56:16 pm

Title: Chromatography
Post by: mandy on February 07, 2010, 05:56:16 pm
A pure substance was suspected of being the high molecular weight anabolic steroid Stanzolol. A sample of this substance was dissolved in a suitable pure solvent and injected into a gas chromatograph. How many peaks would you expect to see in the resulting chromatogram? Justify your answer.

How am I meant to know?
Title: Re: Chromatography
Post by: fady_22 on February 07, 2010, 06:25:11 pm
You should have only one peak, because it is supposed to be a pure substance (therefore only consists of the steroid).
Title: Re: Chromatography
Post by: vexx on February 07, 2010, 06:27:25 pm
You should have only one peak, because it is supposed to be a pure substance (therefore only consists of the steroid).

Yeah the amount of elements in the compound is usually the amount of peaks in a chromatogram.
the no. of compounds in the mixture = the no. of peaks.
heh thanks mao.
Title: Re: Chromatography
Post by: Mao on February 07, 2010, 06:58:21 pm
You should have only one peak, because it is supposed to be a pure substance (therefore only consists of the steroid).

You just beat me.

Yeah the amount of elements in the compound is usually the amount of peaks in a chromatogram.

You meant the number of compounds in the mixture, not to be confused with elements as in elemental compounds [O2, N2, H2, etc]
Title: Re: Chromatography
Post by: vexx on February 07, 2010, 07:17:25 pm
You should have only one peak, because it is supposed to be a pure substance (therefore only consists of the steroid).

You just beat me.

Yeah the amount of elements in the compound is usually the amount of peaks in a chromatogram.

You meant the number of compounds in the mixture, not to be confused with elements as in elemental compounds [O2, N2, H2, etc]

oh sorry, i completely didn't think about it properly.
yep listen to mao, i'll edit my post in case i confuse anyone.
Title: Re: Chromatography
Post by: mandy on February 07, 2010, 08:37:38 pm
Thanks for the help guys :]
Title: Re: Chromatography
Post by: herzy on February 07, 2010, 10:19:24 pm
you're thinking of mass spec :)
Title: Re: Chromatography
Post by: mandy on February 07, 2010, 11:06:21 pm
you're thinking of mass spec :)

oh no, so is it wrong :S
Title: Re: Chromatography
Post by: vexx on February 07, 2010, 11:07:16 pm
you're thinking of mass spec :)

oh no, so is it wrong :S

no what we said above was right.

i think he meant my original comment as mass spec looks at each element. and chromo looks at the compounds in a mixture :)
Title: Re: Chromatography
Post by: mandy on February 07, 2010, 11:11:30 pm
you're thinking of mass spec :)

oh no, so is it wrong :S

no what we said above was right.

i think he meant my original comment as mass spec looks at each element. and chromo looks at the compounds in a mixture :)

Haha, ohhh okay. Thank you!
Title: Re: Chromatography
Post by: herzy on February 07, 2010, 11:26:16 pm
yeah lol sorry for the ambiguity. serves me right for making tired comments wtihout reading the thread properly :)
Title: Re: Chromatography
Post by: longy1991 on February 07, 2010, 11:46:27 pm
but it is "dissolved in a suitable pure solvent", therefore you will get two peaks if it is pure, 1 for the solvent, and 1 for the steroid.