Chemistry: Discussion, Questions & Potential Solutions

[Lear]

what did you get for a systematic error

I think I wrote that the voltage in reality is not constant 6V. It fluctuates.

[jpulvirenti]

same. I mentioned the voltmeter itself

[jpulvirenti]

what about the skeletal formula for the amine?

[tiffanylps09]

what did you get for a systematic error

I said the voltage and current was lower than estimated. Weird wording i know. But i was rushed. Do you think i'll still get a mark?

[jpulvirenti]

I said the voltage and current was lower than estimated. Weird wording i know. But i was rushed. Do you think i'll still get a mark?

I reckon so

[billy606]

what did you get for a systematic error

i said the wires' resistance could have reduced the current hence actually producing less heat energy.

[billy606]

what about the skeletal formula for the amine?

I think it was sort of a triangle with an alkyl (ch2) and nh2 group attached on the top.

[popcorndudette]

No if it was percentage by mass of celloluse it would by 37% which is already given in the question

No I'm pretty sure it was by mass of cellulose... hopefully...

[addictwithatextbook]

Well, that went. 

I'm mad that I took so long and I didn't end up answering 10 marks or something, as I might've overthought the questions. I also spent too long on the amine question because I couldn't find the type of carbon and the other structural isomer until after 10 minutes. I do so awfully in the actual exam but when I do a practice I finish early what's going on

But really I'd rather not answer questions I will most likely get wrong than not answer questions I will most likely get right. I don't even know if my answer on Q1 and Q5 for multiple-choice is right. I don't remember my answer to the cellulose question was it like 113or114/370 x 100 or something

[Lear]

I do so awfully in the actual exam but when I do a practice I finish early what's going on

This is normal. This exam, while very accessible in terms of difficulty, was super long. Found it same length as 2018 NHT exam. Writing speeds will contribute a lot to the separation between A+ and A cut

[Vri123]

No I'm pretty sure it was by mass of cellulose... hopefully...

But they literally gave the percentage by mass of cellulose in the question. It was percentage by mass of the ethanol derived from the cellulose

[Mischi]

This is normal. This exam, while very accessible in terms of difficulty, was super long. Found it same length as 2018 NHT exam. Writing speeds will contribute a lot to the separation between A+ and A cut

Hi Lear!
I was wondering what your opinion is on what the A+ cut would be this year?
Thanks in advance

[vector_graphics]

For the limitations, i wrote that the student didnt rinse the calorimeter and replace the water as some water in the electrical part may have evaporated. would i be correct? and for % of cellulose i got around 31%

[popcorndudette]

But they literally gave the percentage by mass of cellulose in the question. It was percentage by mass of the ethanol derived from the cellulose

Yeah, so dividing by 370kg should yield ~30%?

[billy606]

For the limitations, i wrote that the student didnt rinse the calorimeter and replace the water as some water in the electrical part may have evaporated. would i be correct? and for % of cellulose i got around 31%

im pretty sure it was asking for the limitations of the chemical experiment conducted by student C. In that case would it not be the incomplete reaction of knh3 due to equilibrium?