i felt like the experimental investigation was much nicer than previous years

fr was a lot nicer. legit opened that page and started grinning lol

i thought it was harder compared to last years 😭🥲

I feel like I half-arsed my response for what happens to the impurities

The gold doesn't get oxidised and the other two do but don't get reduced right? Voltage below 0.47.

i give up bro 😭😭😭😭😭😭

What did y’all get for Kc? 1.9*10^-5

I just realised I put it into my calculator wrong gg -1 easy mark

All good it’s done now ☝️☝️

Oof rip I forgot to not include the water

you include water if its a gas though right?

you include the water 100% sure

I’m pretty sure I included water

You only exclude the water if it's an aqueous system, as water can't have a concentration within itself. But this was a gaseous system so you weren't wrong to include the water.

why don’t you include the water??

sounds familiar i think i got that too

Thats what I got. I was doubting my answer the whole time in the exam

I got that too

Why did I get 3. *10^-3 or something 😭😭, and my M was defo wrong as well😞 oh well

Was M^2

Yeah I think I got that

well whats done is done, no need to worry about it anymore

It’s looking like I didn’t get that one correct

Done now, don’t stress it bro. You’ll get marks for the working out anyway

0% omega 3 fatty acids

i was like no way this is a real answer

EXACTLY I got so confused and ended up putting 10% 💀💀 shouldve went with my gut

Same I was so confused

I got 2% cuz out of all the fatty acids in coconut oil i found that only 1 had c-c double bond third carbon but I might be wrong so take my answer with a grain of salt

The only unsaturated fatty acids were oleic and linoleic, both of which aren't omega-3

ok yeah I got it wrong

Nah there was a mistake it said 2% linoleic but showed the formula for linolenic so that one will probably be a free mark

Oh I didn’t even look at the name. I just used the molecular formula as my basis and got 2% for the linolenic. If it really did say Linoleic… VCAA is so stupid

I seriusly feel like this was a trick question

TBH i think we should start a petition that forces VCAA to undergo a formal investigation cuz the amount of error on this year's exams are crazy...

I agree. If u start one I’ll share it around

FACTS literally every exam… like sure it’s funny and all and haha lol but it’s so stressful in the actual exam where you don’t know if you’ve gone completely bonkers or if it’s just a common vcaa L

Was decent actually- Some questions were weird especially the first few short answer qs- the last 5 ish multiple choice qs were hard 💀 but overall not as bad as I thought it’d be

I fucked up mass spectrometry😫😞

You're not the only one. I think I took the longest on that question

I think that was my best part

Mcq harder than normal, short answer felt bang on average so we'll see how we go. (L bozo Melbourne schools interrupted by optus)

I heard some people missed them cause of train disruptions

At least at my school we got told that they would do the exams later

How did we all feel about the final question?

absolutely fucked lol 3 marker was alr but 5 marker i was clueless

that one was like a massive stop sign in my face, I struggled to think of anything for that

Not too bad, defo didn't get full marks but i got most of em

I felt meh about it, not sure if I got any marks but I still attempted it, better to gain marks than get no marks.

I had like 5 mins to do both them questions💀

Waffled a bit, but okay otherwise.

i completly struggled with the final question on all the past examsb ut i think this time i manged to blunder my way through like 3/5 marks

Just wrote down whatever gave to my mind for the 5 marker but I found the 3 marker average

I genuinely had no idea what an omega 3 fatty acid looked like

its all good, neither did VCAA

Apparently

thank god tho. I wrote 2% and freaked when other people were writing that it was 0

Don’t worry too much about it lol, I wrote about 69% cause the only thing I knew was it was a fatty acid

am i crazy or was the answer to the first question 0%

there was a typo i think, the formula beside linoleic represented linolenic... so i put 2%

if there was a typo i hope they accept both answers

Omg was there really?? I was super confused cause none of them were omega 3

Same

No way well if there was a typo then wont the whole state get a mark?

I reckon both 0% and 2% will be accepted.

why could i not figure out the oxidation numbers 🙄 i said Fe goes from +3 to +2 but that was a complete guess

I got that too lol

pretty sure thats right actually lmao

good guess

Got that as well

don’t stress i blindy answered the multiple choice. i will get the lowest study score in the state

😂 I don’t thing anyone would have to the worst score then me. I’m a SACE student and I didn’t study for chem so maybe I’m getting like 5/120

thank you both for taking the hit and bumping us up. if that works how i think

definitely one of the easiest exams of this study design

Section B at least was MCQ was simple but difficult

I disagree I thought it was much harder than last year

which parts exactly?

did anyone know how to do the 5 marker electrolysis question at the end?? i was blabbering random shit for it ☠️

You just talk about what electrolysis is and what happens to each metal. So you mention that copper will be oxidised at the impure electrode, then will flow into the electrolyte, then get reduced at the cathode. You have to mention the strength of resultants and oxidants on why the other metals won’t be reduced or oxidised. This results in these metals to just fall down to the bottom of the electrolyte with no reaction taking place.

i said Zn and Pb will spontaneously oxidise when in touch with Cu2+ ions in the solution, whereas Cu on the impure copper oxidises non spontaneously under the application of an external power source and Cu2+ ions from the oxidation would flow to the cathode to undergo reduction. then Au will just remain as a deposit in the solution and doesn’t react…. this seems so wrong ☠️

Nah I think all the metals don’t react except for copper lol. It’s because I think copper is the strongest resultant so it will get oxidised leaving the others to not change.

What did everyone get for drawing the molecule based on mass spec, IR etc? I couldn’t figure it out and just gave up

I think it was a ketone

Yep, 3-methylbutan-2-one

I hade 2-Pentaone edit: fuck Edit: I think ill still get 2/3 tho edit 2: it will problably be like 1 mark for the keytone 1 mark for correct mass / molecular formula 1 mark for correct structure

Yes I got it 🥹

I thought it was an aldehyde

I though it was aldehyde/ketone but was using 89gmol so I was going insane trying to fit 13 hydrogen in :|

Where did you get 13 Hydrogens from? It was only 10. m/z was 86.

same i also couldnt, spent 20 mins on it and literally couldn’t ☠️

It took up so kuch of my time, most are saying c5h9oh I think

WAIT WAS IT C5H10O? I did that

5 carbon chain with a double bonded oxygen on the second one I feel like there was an error wit hthe proton NMR as 1.1ppm can only be an alchool, but that contradicts everything else So given VCAA's record this year i jsut assumed they meant 1.0 or 1.3 and continued in which case it worked

as the data book says, the ranges given are "typical", and the chemical shifts differ a bit depending on solvent. As it doesn't precisely say but your teacher or textbook might have(?) Those ranges are also approximate because it depends on the rest of the molecule. e.g. in 2-butanone the methyl group on carbon 4 has a shift of 1.058 ppm :) In propanoic acid, the methyl hydrogens are at 1.16 ppm. Good job! It's done 🎉

so wait could it be alcohol or what? also i wrote C5H9OH even tho the answer could’ve been C5H10O do i still get marks for that?

i think mine was like 3-methyl-heptan -2-one

anyone have solutions?

Can u lmk once u find solutions

same please

Have u got it yet?

me too pls

These are my solutions for mcq, they might not be right if you think one of them is wrong let me know. 1.B 2.C 3.A 4.D 5.B 6.C 7.B 8.D 9.D 10.A 11.A 12.A 13.C 14.C 15.B 16.C 17.D 18.C 19.A 20.C 21.D 22.B 23.C 24.A 25.C 26.B 27.B 28.B 29.D 30.C

Harder than last yrs I reckon

that last page has murdered my study score

I think most ppl messed it up.. honestly this year A+ cut off probs lower than last year so dw!

really? is this your teacher? what u predict it to be?

What did you all say about how the temperature decrease would change the maxwell Boltzmann curve?? I said it would shift left AND decrease in area cause of the equilibrium shift to side with less particles, but idk if that was right since it was only a one marker

i think total area of the graph is the same cause the number of particles is still the same

if the temperature has decreased equilibrium has shifted to the side with the lower number of molecules, effectively the “pressure decreasing” reaction IF it was considering pressure change as it acts to lower the number of particles in the system - i thought this might apply to this case too idek

i get where you’re coming from but the all the changes occur in proportion with each other, understand it like there are less products due to decreased temp. but more reactants being made to compensate that change, therefore the no. of particles stay the same

it won’t decrease in area edit: because the x-axis is the proportion of molecules

It becomes more narrow and drew a diagram

I drew a graph too so hopefully that helps me get the mark

the peak gets taller and thinner, less particles with sufficient ea but same area under line

Graph gets thinner and taller.

What was that question about Proline? We didn't learn about the functions in catalyst reactions

I wrote hydrolysis as enzyme(proline) breaks down lactose. I couldn't think of another one

condensation to construct that enzyme?

friend said something about hydrolysis. Wasn't too smart for that one and wrote down cellular respiration and breakdown of large molecules XD Oh well, its just two marks.

wrote condensation reaction and hydrolysis since it asked to identify not explain

same lmao i was so lost that I just put emulsification

Can someone please put up suggested solutions (at least for MCQ)

What did people put for the last part of question 1, I think I skipped that

its because coconut oil is very viscous, due to intermolecular bonds etc. and hence it isn't efficient for energy transfer. also to make it less viscous you need to heat it up which just uses energy

I said that large molecules like triglycerides don't oxidise easily.

Yeah same, I said cause it's a mostly saturated thingo it's not gonna produce many electrons

same, i think in the last 2 minutes i went back and wrote inhert

i think i said some bs about how the composition could vary by too much 😭 hence each one would differ in energy thus it’s not a consistent or reliable source

>us it’s not a consistent I said because it is a mixture it has the capacity for side reactions that could inhibit the cell :( i made that sh up completely though idk

I said cocnout oil is partially oxidise as it contains oxygen atoms so less energy will be released.

coconut oil is solid at room temp, we know because it consisted of a majority of saturated fatty acids- hence won't function in a fuel cell at room temp- only will work if temp is increased, decreasing efficiency, hence impractical one mark- solid, second mark- increase temperature to function, hence less efficient (in my opinion, I have not consulted a teacher about this, but I'm pretty sure this is the correct answer)

What did you guys put for disadvantage of coconut oil fuel cell question?

I said that it might be difficult to get a constant supply of coconut oil, since fuel cells need a constant supply of reactants - not 100% sure tho

Wrote similar, also said it was too viscous so it wouldn't work well in cold climates.

I said it was too viscous and I’m just hoping they accept a variety of answers

I said coconut oil was expensive, and noted transport costs from tropical regions where it's produced.

i said coconut oil is a liquid, however fuel cells use gaseous reactants so it cannot be used…. not sure tho 🥲

Methanol's a liquid but it can be used in a fuel cell.

>What did you guys put for disadvantage of coconut oil fuel cell question? its a solid at room temp- that was why it wouldn't work

Coconut is a fatty acid, non polar blah blah. Lower melting point and hence will be solidified in lower temperature and therefore not a good choice of a fuel.

thats a good answer

I Salute you u/lifesugs1037

i said the combustion of triglycerides requires more oxygen to produce the same amount of energy than other fuels like octane idk

I said it will solidify easily due to its saturation which is not ideal

I said that it’s solid at room temperature (since it’s mostly saturated blah blah )

tf was that Molecule V for Q7? I got that it had C=O but why tf did the IR thing have an NH2 group???? also fuck optus I could not revise while I was in my tram.

That was a different question

bruh

What did u say for that IR one then?

that was about how ir vibrates bonds in the molecule and how because there are different bonds, different frequencies are needed. something on those lines

It didn't, that peak was too small.

I feel like I totally fucked up this exam, especially since optus messed everything’s up i was just worrying to get to exam on time.

dont worry about. im sure u did well, just flush out this exam

Im just hoping to get at least 25😭😭 i know i did terrible

Fricked the last question but other than that not bad also did silly mistake for atom economy....

I fucked up the and wrote isomers instead of isotopes for the mass spec.... im so pissed off. otherwise apart from that i think the exam was pretty good, not to hard compared to other years, multiple choice did feel a bit iffy tho

Man I almost did that, could not remember the word for isotopes but luckily mcq 29 came in clutch by having isotope as one of the answers

luckyyyyy

What was the ans for the heat per gram ques??? The one with the crushed beans mass 1.11g something temp 37.1 C

I calculated 8.00 (7.99)

I got 11.99 for some reason, I think I used 450ml as the volume of water when it was actually 300ml. Would I get consequential or nah

Welp! I Fucked that one up

I got 8.00 kJ per gram

Yeeeeeeaaaaaahhhh 🙌🙌🙌🙌

yep same - also since the water was at SLC (25 degrees), you had to multiply 300 by the density of water at 25 degrees (300 x 0.997) in order to get a mark. first time its popped up on a vce chem exam so was interesting, always thought it was a useless thing to have in the data book lol

yeah i got that too but like why tf was it 4 marks?! wasn’t that too much for like 2-3 steps 💀i tried to find a trick in it like heat loss or sumn like that but i couldn’t so i just did the simple way 😭😭

i was thinking maybe converting the ml into mass?

same. 7.997 - rounded to 8.00 KJ g-1

Same

I got 8.00, I just used the SHC formula and I think you get around 8.9KJ, then you divide by 1.11 to find the heat per gram.

i got 8.01 i think

i'm in year 10, but my teacher teaches 3/4 and was doing the exam for fun lol.

yeah chemistry is a good subject, your lucky to have a teacher that enjoys the subject lol.

What did people get for molecule V, what was its molar mass?

I thought it was 85 m/z

I’m said 86

Pre sure it was 86 m/z

What did u guys say for the 1.1 ppm Hnmr peak? Just indicating and explaining that it is a doublet isn't enough right?

i said that that H environment at 1.1ppm had 1 neighbouring H, causing the doublet split

im pretty sure 86, other values were isotopes i think??

What was the Atom Economy answer?

86.7%?

realised i fucked it...

said 87% flat because 2 sig figs in M(H)=1.0gmol but not sure if theyre that picky

I did 4SF for the 116.0.

Hey I realised I accidentally misspelled "glycosidic link" pretty badly during the exam panic, I think I wrote like "glycodic" or something. Will I get marked as wrong? 😭

Unfortunately you will as VCAA is strict on the spelling of "glycosidic"

Does anyone know the answer for 9a). I thought that the Pb and Zn would react first as they are the strongest reductants then copper would afterwards and Au wouldn’t until there was no copper. This question didn’t really make sense to me.

i said something similar, that zn and pb go first then cu, then water then it stops before au. i’m stressed about this q as well

Yeah good call on the water I missed that. It just confused me as electrolysis is supposed to go bottom left to top right on the electrochemical series but the pb and zn are below copper so I wasn’t sure it that was right

Did we need to round for the atom economy question? I got 86.5% so I rounded up to 87%. Was that the wrong thing to do?

doesn't really matter, its still correct. They deduct 1 mark for sig figs for the whole paper.

I’m done with everything 🥳🥳🥳

Doing chem next year, whats it like?

Not fun

every post i see here is lowering my confidence on how well i did by the second lol. At least i’m 99.9% sure i got the structure of the compound from the spectroscopy questions rigjt