HSC Chemistry Exam Solutions / Thoughts (3 Viewers)

[Arrowshaft]

nah I think the moderators merged the threads

Oh right makes sense

 

[Idkwhattoput]

Sorry about that. Didn't realise there was already a thread

 

[Idkwhattoput]

Hi everyone,
Hope your preparation for the Chemistry Exam is going well

Post any predictions you have below. This is the first year of the new Chemistry HSC syllabus so it will be interesting to see how NESA will structure the new papers

Also share any thoughts or solutions for the exam

Also: If anyone has a copy of the paper after the exam, if you send it to me I will write up a comprehensive set of solutions

Apart from trials, I've never really done a timed chem paper. Should I be worried about time, or is that usually not a problem in the sciences? I know that obviously I need to be efficient, but does time play a major role in the difficulty of the exam? I know it varies from student to student, but if it helps I'd predict I'm roughly a high band 5 student.

 

[jazz519]

Apart from trials, I've never really done a timed chem paper. Should I be worried about time, or is that usually not a problem in the sciences? I know that obviously I need to be efficient, but does time play a major role in the difficulty of the exam? I know it varies from student to student, but if it helps I'd predict I'm roughly a high band 5 student.

Not too sure to be honest because we haven’t seen yet a full paper from NESA to show how many questions they will ask and the mark allocation. But in old syllabus it wasn’t that much of a problem. I would just say to you don’t go slowly try to set time goals in the exam I.e how many marks you wanna finish off by a certain time to stay on track to finish

 

[Idkwhattoput]

Not too sure to be honest because we haven’t seen yet a full paper from NESA to show how many questions they will ask and the mark allocation. But in old syllabus it wasn’t that much of a problem. I would just say to you don’t go slowly try to set time goals in the exam I.e how many marks you wanna finish off by a certain time to stay on track to finish

Fair enough. I'd assume it'll be similar to the old syllabus. Thanks

 

[Arrowshaft]

Do you think it’s a good idea to leave the two 7-9 markers to the end and finish the rest of the paper first? What would you have done? Thanks, Jazz

 

[jazz519]

Do you think it’s a good idea to leave the two 7-9 markers to the end and finish the rest of the paper first? What would you have done? Thanks, Jazz

Either order is fine but usually recommend do all the things you know first off so you do those fast and gain extra time to do things you don’t understand quite as well or are hard questions. For the 7-9 markers try to pace yourself. Usually for those during reading time you should think about what you can write about then as writing time starts just jot down what you are going to discuss in dot points (that will give you a plan of attack for those questions)

 

[jazz519]

I think the 7-9 markers aren’t going to be something like just write and write. My prediction is it will be some type of application question likely from the spectrums in module 8, reaction pathways in module 7. That is just my guess based on like the bio paper which had a lot of tables of data analysis

 

[AHafza]

I think the 7-9 markers aren’t going to be something like just write and write. My prediction is it will be some type of application question likely from the spectrums in module 8, reaction pathways in module 7. That is just my guess based on like the bio paper which had a lot of tables of data analysis

Definelty I think so too

 

[AHafza]

I think the 7-9 markers aren’t going to be something like just write and write. My prediction is it will be some type of application question likely from the spectrums in module 8, reaction pathways in module 7. That is just my guess based on like the bio paper which had a lot of tables of data analysis

I predict the environmental, economical, and sociocultural stuff along with fuels will be short 4 makers where u just need to make a few points

 

[AHafza]

Even the chemical process stuff about the factors... maybe a 5 marker

 

[Arrowshaft]

Even the chemical process stuff about the factors... maybe a 5 marker

Agreed. Probably like the Haber process question in the sample questions. I feel this test is more testing analytical skills and critical thinking. So I reckon they’ll provide the info and we’ll have to make a judgement based on that.

 

[Arrowshaft]

I predict the environmental, economical, and sociocultural stuff along with fuels will be short 4 makers where u just need to make a few points

What have you memorised for those? I did biodiesel and bioethanol. I don’t know to what extent they’re gonna test it though, like I memorised transesterification of biodiesel but feel it’ll make my answer too convoluted, so might just mention it briefly. The sociocultural impacts stumped me though, I just had some bogus arguments about stress and over reliance on non renewables, but idk

 

[AHafza]

What have you memorised for those? I did biodiesel and bioethanol. I don’t know to what extent they’re gonna test it though, like I memorised transesterification of biodiesel but feel it’ll make my answer too convoluted, so might just mention it briefly. The sociocultural impacts stumped me though, I just had some bogus arguments about stress and over reliance on non renewables, but idk

For sociocultural speak about the dangers to human labour, sulfate fumes, speak about the wars that could possibly occur over the possession of fuel, and how humans are reliant on fuel...

 

[AHafza]

What have you memorised for those? I did biodiesel and bioethanol. I don’t know to what extent they’re gonna test it though, like I memorised transesterification of biodiesel but feel it’ll make my answer too convoluted, so might just mention it briefly. The sociocultural impacts stumped me though, I just had some bogus arguments about stress and over reliance on non renewables, but idk

I’ve just memorised 2 points per impact, and for fuels; renewable vs non renewable, bioethanol vs ethanol, and different petrols, like octane vs ethanol.

 

[AHafza]

Agreed. Probably like the Haber process question in the sample questions. I feel this test is more testing analytical skills and critical thinking. So I reckon they’ll provide the info and we’ll have to make a judgement based on that.

So it would prob be something on equilibrium and the hater process. Maybe optimum conditions for max yield?

 

[Idkwhattoput]

I think the 7-9 markers aren’t going to be something like just write and write. My prediction is it will be some type of application question likely from the spectrums in module 8, reaction pathways in module 7. That is just my guess based on like the bio paper which had a lot of tables of data analysis

I REALLY hope so. I hate extended response questions because its so hard to know what the markers are looking for and for that reason they are relatively bad indicators of your chemistry skill imo.

 

[jazz519]

Just a piece of advice with those society questions. Technically it is a society, economics etc question BUT what the examiners are actually looking for there is not your understanding of like saying things are renewable or making blanket statements. They are more looking for are you able to link the chemistry you have learnt to a society, environmental or economics issue.

For instance if someone just said ethanol is renewable I wouldn't be inclined to give that a good mark. There's no link to the chemistry you have learnt. A better answer would be ethanol is renewable when derived from plants such as maze or sugar cane. This provides a glucose source which can be used in fermentation (INSERT CHEMICAL EQUATION)

That there is a way better way to justify something

Another example, if I am talking about an advantage to the economy of fossil fuels. Lets say I say something like fossil fuels are used in a variety of places that improve human life such as home appliances, fuel sources, agriculture, stoves and heating. You can make your answer better and link it to the chemistry, by saying what the specific hydrocarbons are used in each application. So for example methane in stoves (EQUATION), fuel sources use octane normally (EQUATION), agriculture uses diesel (EQUATION), coal for electricity (EQUATION)

One last example, ethanol has a disadvantage to economics in terms of cars as water gets dissolved in it which will corrode engines. Here is a perfect opportunity for you to discuss your knowledge on intermolecular forces. So add in your answer, ethanol is a polar molecule and has dipole-dipole interactions as well as hydrogen bonding which allows water to dissolve in it (CAN EVEN STICK IN THE DIAGRAM HERE SHOWING THE HYDROGEN BOND BETWEEN ETHANOL AND WATER). This is a problem for a fuel source because water is corrosive to metals in the engine lining (EQUATION here for rust if you know it)

So make sure you don't just write a million words in those questions try to attach chemical equations and chemistry principles everywhere

 

[Arrowshaft]

So it would prob be something on equilibrium and the hater process. Maybe optimum conditions for max yield?

I don’t think it’ll be Haber since they already asked it, maybe Contact process and asking you to discuss the effect of each reaction

 

[Idkwhattoput]

Just a piece of advice with those society questions. Technically it is a society, economics etc question BUT what the examiners are actually looking for there is not your understanding of like saying things are renewable or making blanket statements. They are more looking for are you able to link the chemistry you have learnt to a society, environmental or economics issue.

For instance if someone just said ethanol is renewable I wouldn't be inclined to give that a good mark. There's no link to the chemistry you have learnt. A better answer would be ethanol is renewable when derived from plants such as maze or sugar cane. This provides a glucose source which can be used in fermentation (INSERT CHEMICAL EQUATION)

That there is a way better way to justify something

Another example, if I am talking about an advantage to the economy of fossil fuels. Lets say I say something like fossil fuels are used in a variety of places that improve human life such as home appliances, fuel sources, agriculture, stoves and heating. You can make your answer better and link it to the chemistry, by saying what the specific hydrocarbons are used in each application. So for example methane in stoves (EQUATION), fuel sources use octane normally (EQUATION), agriculture uses diesel (EQUATION), coal for electricity (EQUATION)

One last example, ethanol has a disadvantage to economics in terms of cars as water gets dissolved in it which will corrode engines. Here is a perfect opportunity for you to discuss your knowledge on intermolecular forces. So add in your answer, ethanol is a polar molecule and has dipole-dipole interactions as well as hydrogen bonding which allows water to dissolve in it (CAN EVEN STICK IN THE DIAGRAM HERE SHOWING THE HYDROGEN BOND BETWEEN ETHANOL AND WATER). This is a problem for a fuel source because water is corrosive to metals in the engine lining (EQUATION here for rust if you know it)

So make sure you don't just write a million words in those questions try to attach chemical equations and chemistry principles everywhere

Very helpful. Thanks