VCE Chemistry 2010 Unit 3 Exam Suggested Solutions

[Twenty10]

tbh this exam was probably worse than last year. not because I think I did bad but more so because it didn't test about your level of chemistry but more about how many tricks they tried to fit into the exam. Feels like their main intention wasn't to test our chemistry knowledge but more to pick the ones who make the silly mistakes.

Yep.. and the worst part is teachers tell you about how the exam is designed to test your knowledge and not to trick you. Turns out they where wrong. X|

[crayolé]

True, something like last year was perfect, why did they have go down that path

[samiira]

when do our results come..??

[vexx]

do you think that vcaa could ever give consequential marks for a misinterpreted question? like quite a few people got the last question wrong as they thought it meant something else - could they get a mark for the explanation but a mark off for the actual answer? or definitely get both wrong?

[Blakhitman]

when do our results come..??

August 2nd!

[Studyinghard]

True, something like last year was perfect, why did they have go down that path

i think they just got annoyed because everyone complained that last year was too hard so now they just wanted to have some fun. =[

[darkphoenix]

last year wasnt even that hard? i just reckon no one was ready coz they had a simple 08..

Some of the 'interpreting' ones were kinda tricky, but yeah they didn't have much to practice on, so yeah made it harder.

[Studyinghard]

last year wasnt even that hard? i just reckon no one was ready coz they had a simple 08..

Yeah but people still complained about it. Im not saying it was hard. heck I would have preferred last year's exam compared to this year.

[will74]

shitt did we have to write OH- for Question 8bii....i wrote OH, no minus

[kenhung123]

do you think that vcaa could ever give consequential marks for a misinterpreted question? like quite a few people got the last question wrong as they thought it meant something else - could they get a mark for the explanation but a mark off for the actual answer? or definitely get both wrong?

The explanation for the last question works both ways assuming the misinterpretation meant your didn't know which mixture.

[Studyinghard]

shitt did we have to write OH- for Question 8bii....i wrote OH, no minus

Nope I dont think we had to write -OH. it doesnt even make sense for it to be negatively charged in the molecule.

[kenhung123]

Yea, its not meant to be negatively charged

[8039]

For question 3... wouldn't it be 2e-?

The original electron AND the one knocked off?

[kenhung123]

On the right hand side, yes

[year12]

Mao can you explain your reasoning behind your answer of 2 for the question: "The signal at 1.3 ppm is split into a triplet. What is the number of equivalent protons bonded to the adjacent carbon atom?" (Page 13)

n+1 rule
3 peaks means it's got two adjacent hydrogens

But to form splits in the peaks, the hydrogens have to be in different environments , i.e. in non-equivalent environments. Which means there are zero protons bonded to the adjacent carbon that are equivalent.

From KBT solutions :"If the hydrogens of a particular environment have n neighbouring, non-equivalent hydrogens,
the peak from that environment will be split into n+1 component peaks.
Keep in mind that the word ‘neighbouring’ as it’s used above means ‘on the adjacent carbon
atom’. ‘Non-equivalent’ means ‘not of the same environment’."
(http://www.kbtlectures.com/wp-content/uploads/2010/04/KBT_unit3chemistry_trialexamsolutions.pdf)

Yes, I agree! I wrote '0 (none)' yesterday as well because of the question didn't say 'NON-equivalnet'.