VCE Chemistry 2010 Unit 3 Exam Suggested Solutions

[vexx]

im pretty sure the invertase question was optimum at 55 degrees. And i've looked up invertase and its optimum temp is around 60 degrees and its optimum pH around 4.5??

this is vce land, we don't require outside knowledge (from our vce course ;] )
the optimum temp according to that graph was 35, look at it againnn.

[will74]

it says in the Q that it 'operates at different temps to many enzymes' i.e body temp=around 35 so you would expect invertase to be different

[Studyinghard]

im pretty sure the invertase question was optimum at 55 degrees. And i've looked up invertase and its optimum temp is around 60 degrees and its optimum pH around 4.5??

this is vce land, we don't require outside knowledge (from our vce course ;] )
the optimum temp according to that graph was 35, look at it againnn.

dude look at the key of the graph. its a bit tricky. its 55!

[10weid]

whats the verdict? states needed for mass spec quesiton or not?

[Stroodle]

yeah, the scan is all screwed up

[will74]

if you have the scanned copy of the exam its hard to see but it was 55

[stonecold]

highest line = triangles

triangles = 55 degrees.

[vexx]

im pretty sure the invertase question was optimum at 55 degrees. And i've looked up invertase and its optimum temp is around 60 degrees and its optimum pH around 4.5??

this is vce land, we don't require outside knowledge (from our vce course ;] )
the optimum temp according to that graph was 35, look at it againnn.

dude look at the key of the graph. its a bit tricky. its 55!

oh sorry haha yeah it is 55, i just looked at it again, my memory isn't my friend right now >_>

[jake]

we were taught that concordant titres must lie within 0.02ml of each other, and if there is only two that do, then just use those two and justify "+/- 0.02ml". if this isn't right, then i'll be so upset.. hah

and people it's definitely 35 degrees for that question since it has the highest reaction there, annnnnnd i was quite sure states were needed and stated at the start of the exam. it should be known that in mass spec everything is vaporised before ionisation.

same...

That's what I did!

99% sure its 55 degrees. look carefully the key for 35 degrees is diamond in shape and the key for 55 degrees is triangular. the graph at the top (most activity) has triangles NOT diamonds and is hence 55 degrees not 35. sorry guys

[will74]

hey is this wrong for mass spec

CH3CH2OH + e- >>>> CH3CH2OH+   + 2e-

including the bombarding electron?

[vexx]

sorry again, i should really have double checked the paper before i assumed that mao had read it right xD

will: that is correct, it is what the books says.

[Blakhitman]

we were taught that concordant titres must lie within 0.02ml of each other, and if there is only two that do, then just use those two and justify "+/- 0.02ml". if this isn't right, then i'll be so upset.. hah

and people it's definitely 35 degrees for that question since it has the highest reaction there, annnnnnd i was quite sure states were needed and stated at the start of the exam. it should be known that in mass spec everything is vaporised before ionisation.

same...

That's what I did!

99% sure its 55 degrees. look carefully the key for 35 degrees is diamond in shape and the key for 55 degrees is triangular. the graph at the top (most activity) has triangles NOT diamonds and is hence 55 degrees not 35. sorry guys

I was talking about the concordant titre lol.

[crayolé]

You didnt do 35 in the exam did you vexx? :/

[kenhung123]

For the question where you needed to find the formula for compound X is it wrong if you gave it in the form CnH2n-11COOH

[will74]

sorry again, i should really have double checked the paper before i assumed that mao had read it right xD

will: that is correct, it is what the books says.

cheers