VCE Chemistry 2010 Unit 3 Exam Suggested Solutions

[chansthename]

Meh, atm I concede 2 marks. I'm just praying that I filled out the MC answer sheet right.

I also pray that a bug crawls into my paper and takes a shit on page 21, right in between the 1 and the 5 so it looks like there is a decimal point and reads 1.5 L haha...

Same, 2 marks from multi but there is a short answer that I am sceptical of, just hope I did the right thing, still at worst on that specific question 1 mark.

[Blakhitman]

Any chance of 40 with high A/low A+? what would be required end of year?

[Russ]

35/36?

Haven't been around the VCE system for a while now, but with a very strong end of year mark you could do it. (that's only my opinion though, someone else more familiar could give a better estimate)

[rubiks]

Haven't been around the VCE system for a while now, but with a very strong end of year mark you could do it.

So I'd basically need to get an A+ to get it?

[Studyinghard]

Haven't been around the VCE system for a while now, but with a very strong end of year mark you could do it.

44 scaled? so like 41 raw???!?!?!?!?!

[chansthename]

Mao, for question 7bii, can you write a note that a formula in the cxhycooh or any other correct formula should be acceptable (It doesn't say molecular formula, just formula)

thanks

[Russ]

44 scaled? so like 41 raw???!?!?!?!?!

Can't remember, sorry. Why does it matter?

So I'd basically need to get an A+ to get it?

Depends whether you meant raw or scaled actually, scaled will obviously be less. But 35/36 is achievable with a B+ on the midyear (from my experience with one of my subjects :S)

[rubiks]

I meant raw. What do you think I'd be looking at if I were to get an A on the end of year and A for SACs?

[Russ]

I meant raw. What do you think I'd be looking at if I were to get an A on the end of year and A for SACs?

I have no idea, but I ran it through ENTER calculator and based on the 2008 scaling reports an overall B+ is between 32-36. So if you had B+ and an A, it would be skewed towards the upper end of that interval.

Talk to your teacher though, they'll have a more accurate idea

[rubiks]

I meant raw. What do you think I'd be looking at if I were to get an A on the end of year and A for SACs?

I have no idea, but I ran it through ENTER calculator and based on the 2008 scaling reports an overall B+ is between 32-36. So if you had B+ and an A, it would be skewed towards the upper end of that interval.

Talk to your teacher though, they'll have a more accurate idea

Ok, thanks. That makes me feel a little better lol

[s2lindah]

THANKS MAO!
Ouch.. I forgot all about sig figs... would that be -1 off for every question?

[stonecold]

THANKS MAO!
Ouch.. I forgot all about sig figs... would that be -1 off for every question?

Nah just one mark on the whole paper.

[bubsy]

Wasn't question 9.a asking about the alkanols in the mixture collected once it had been distilled?

THAT'S WHAT I THOUGHT SJKHDSKHSDHKFSKHSFDHFHSKJ AMBIGUOUS WORDING
"The first fraction is collected at 97.2 degrees."
"Identify one alkanol which could not be present in this mixture."

>________<
I read it as a connected sentence, not realising that the "mixture" referred to the actual mixture of compounds. Hate.

[Mao]

Could you say not to use a bunsen burner as you have no control over the termperature Mao?

No, the temperature can be easily controlled by using adjusting the flame while looking at a thermometer.

but it changes constantly doesnt it? you cant exactly "control" the flame.

You can, by controlling the gas flow rate (there's always a valve there).

The misconception here is if you want to heat the gas to 90 degrees, the heat source must be 90 degrees. This is not true, the heat source is always a lot higher, even if a hot plate is used. The amount of energy delivered is dependant on both the temperature and the size of the heating source. Using a heat source of 300 degrees will not necessarily heat the mixture to 300 degrees, and if the size of the heat source is controlled, you can either heat it up rapidly (high flame) or slowly (low flame).

Another thing to consider is latent heat of vapourization (the temperature of a mixture stays constant if a component is vapourizing).

[johsephhh_]

for 7 b ii i put C21H31COOH is that still correct?