ATAR Notes: Forum
VCE Stuff => VCE Science => VCE Mathematics/Science/Technology => VCE Subjects + Help => VCE Chemistry => Topic started by: destain on June 12, 2012, 12:19:12 pm
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1) I've always had some sort of a problem splitting up structures for identifying fragments in IR spec...
HCOOCH(CH3)2
Can't that split into OCH(CH3)2 for a peak at a m/e ratio of 59?
It adds up to 59 hah but yeah i know it looks weird...and someone can tell me the best to identify fragments please :(
2) 3-bromo-2-methyl-pentane
or 2-methyl-3-bromopentane? which is right...
3) Also glucose can be broken down to produce alcohol, name this type of reaction.
I did fermentation
but the answers say Oxidation or redox
and then give the fermentation equation...Is that also right or something?
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for number 2, its definitely 3-bromo-2-methyl pentane, always do functional groups in alphabetical orer
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1) I've always had some sort of a problem splitting up structures for identifying fragments in IR spec...
HCOOCH(CH3)2
Can't that split into OCH(CH3)2 for a peak at a m/e ratio of 59?
It adds up to 59 hah but yeah i know it looks weird...and someone can tell me the best to identify fragments please :(
2) 3-bromo-2-methyl-pentane
or 2-methyl-3-bromopentane? which is right...
3) Also glucose can be broken down to produce alcohol, name this type of reaction.
I did fermentation
but the answers say Oxidation or redox
and then give the fermentation equation...Is that also right or something?
3- Was this from a trial exam- if it is, I would say yes fermentation would also be correct (if it was VCAA, then I guess not)
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It was and yes it might be wrong but just asking if it might also be called that maybe..
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Just to confirm, reactions between alkanes and fluorine gas don't require a catalyst like alkanes and chlorine/bromine gas, right?
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Whats the catalyst for bromine gas?
and i don't think i've come across a reaction between flurione and alkanes .. LOL
and between isomers do physical AND chemical properties change or just physical?
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Chemical properties too. For example only primary alcohols can be oxidised to give carboxylic acids, and tertiary alcohols can't be oxidised at all.
I think the catalyst for bromine gas is light as well.
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what does hydrogenation do in a triglyceride
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what does hydrogenation do in a triglyceride
converts the unsaturated fatty acid component into a saturated fatty acid
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1) I've always had some sort of a problem splitting up structures for identifying fragments in IR spec...
HCOOCH(CH3)2
Can't that split into OCH(CH3)2 for a peak at a m/e ratio of 59?
It adds up to 59 hah but yeah i know it looks weird...and someone can tell me the best to identify fragments please
that split is definitely possible
2) 3-bromo-2-methyl-pentane
or 2-methyl-3-bromopentane? which is right...
3-bromo-2-methyl-pentane is right, always alphabetical order
3) Also glucose can be broken down to produce alcohol, name this type of reaction.
I did fermentation
but the answers say Oxidation or redox
and then give the fermentation equation...Is that also right or something?
fermentation is right lol, but the fermentation itself is an oxidation but you should be able to say fermentation
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3) Also glucose can be broken down to produce alcohol, name this type of reaction.
I did fermentation
but the answers say Oxidation or redox
and then give the fermentation equation...Is that also right or something?
fermentation is right lol, but the fermentation itself is an oxidation but you should be able to say fermentation
You should really say oxidation, in bio 'fermentation' would be fine, but oxidation is more correct in chem
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You should really say oxidation, in bio 'fermentation' would be fine, but oxidation is more correct in chem
Pfft they'd call it fermentation in biochem :P That's chem!
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Chemical properties too. For example only primary alcohols can be oxidised to give carboxylic acids, and tertiary alcohols can't be oxidised at all.
I think the catalyst for bromine gas is light as well.
Well that's not entirely true. Tertiary alcohols can be combusted and this is technically oxidation.
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Touche.
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haha, would i be able to write on a vcaa exam, tertiary alcohols cannot be oxisdised at all?
so scared.........
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An aqueous solution of nitric acid was titrated against a 0.100M solution of sodium carbonate. A 20.00ml aliquot of this sodium carbonate solution was pipetted into a conical flash and titrated against 0.0500 mol/L nitric acid solution.
Calculate the volume, in ml, of the 0.0500mol/L nitric acid added to the aliquot of sodium carbonate.
Either this question can't be done or I'm just being retarded... Probably the latter of the two aforementioned scenarios.
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2HNO3 + Na2CO3 --> 2NaNO3 + H2O + CO2
n(Na2CO3)=0.02*0.1=0.002mol
We need twice the amount of HNO3 as we do sodium carbonate so we require 0.004mol of nitric acid.
V=n/C so 00.4/0.05 = 0.0800L
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In vcaa 2011, i had problems with sig figs.
In sa question 5, the smallest value of sig figs was 0.0525, so i thought it was gonna be three sig figs all the way through, then in the assessment report, bii and biii were four sig figs? How does this work???
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If in that question, the least number of sig figs in the information that you used was4 sig figs
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but the smallest amount of sig ffigs was three?
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that you used in answering your question? the particular bii) or whatever it was bi)
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Is it likely that we will be required to draw a absorbance graph?
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calibration graph? half the time i guess
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If we have to draw it the line of best fit can start at the lowest y-value (absorbance value/peak area) and finish at the greatest y-value (absorbance value/peak area) right?
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I meant are we likely to get a question like the one on page 29 of the ATAR Notes chem book.