HSC Chemistry Exam Solutions / Thoughts (1 Viewer)

[Arrowshaft]

Wtf, isn't accounting for x the more correct thing to do? Although I think I landed on the same answer. Or a very similar one at least. Eh, I think it should be fine tbh.

You gotta realise. Some chemistry students also do ge.. gen.. genn... genny maths

 

[englishessayssuck]

Wait lmao if I didn't assume that x is negligible for a pH question, am I going to lose marks? Boi I literally used quadratic formula to be extra accurate, LOL.

I also did the quadratic formula method just to make sure the answer agrees with the "estimated" one (by a lot of decimal points), so probably no chance that will lose a mark (assuming of course you set out the quadratic equation properly idk)

they'll probably be looking more to see if people have the correct number of sig figs tbh for a pH question

 

[Arrowshaft]

Wtf, isn't accounting for x the more correct thing to do? Although I think I landed on the same answer. Or a very similar one at least. Eh, I think it should be fine tbh.

Nah but on a serious note, you’ll get 0. Jk, you won’t lose any, it’s just the quadratic formula, not like you performed a contour integral of the molecules over a Gaussian surface and then used Stokes’ Theorem to find the meaning of life

 

[Arrowshaft]

What exact marks are we aiming for?

 

[Arrowshaft]

Did you guys mention the inability to explain the acidic and basic natures of certain oxides, and AlCl3 and BF3 for the Bronsted-Lowry question?

 

[englishessayssuck]

Did you guys mention the inability to explain the acidic and basic natures of certain oxides, and AlCl3 and BF3 for the Bronsted-Lowry question?

yeah that and the sulfur trioxide reaction with calcium oxide

 

[Arrowshaft]

yeah that and the sulfur trioxide reaction with calcium oxide

What reactions did you include?

 

[Idkwhattoput]

Did you guys mention the inability to explain the acidic and basic natures of certain oxides, and AlCl3 and BF3 for the Bronsted-Lowry question?

Yeah but I didn't give any examples. Not expectating to get a great mark for that q tbh. 3/5 would be nice

 

[Arrowshaft]

Yeah but I didn't give any examples. Not expectating to get a great mark for that q tbh. 3/5 would be nice

No examples at all? Not even the ammonium chloride vapours?

 

[Idkwhattoput]

What exact marks are we aiming for?

I definitely lost 7 marks to silly mistakes/forgetting things. I finished pretty early and got to scheck my paper multiple times, but I reckin I lost another 8 or so marks. So 85+ is the goal. But I'm not gonna lie, anything that gets 90 aligned will be fine for me

 

[Arrowshaft]

I definitely lost 7 marks to silly mistakes/forgetting things. I finished pretty early and got to scheck my paper multiple times, but I reckin I lost another 8 or so marks. So 85+ is the goal. But I'm not gonna lie, anything that gets 90 aligned will be fine for me

That’s easy 90 mate. Considering how usually 7% of the state gets a band 6 and most chemistry students don’t do higher level maths, also considering this is Board of Studies lol, you’ll get that band 6. I’m sure youre top 7%

 

[Idkwhattoput]

No examples at all? Not even the ammonium chloride vapours?

No I only gave equations for Bronsted lowry acids and bases (sodium hydroxide and hydrochloric) because I didn't want to accidentally give an incorrect neutralisation equation. I feel like I gave a lot of info for that, but I didn't give specifics unfortunately. Luckily the exam was relatively maths heavy cause I cant do extended responses for shit

 

[worldno17]

What reactions did you include?

not the person u quoted (but procrastinating on physics right now....) but I did the CaO reaction like the person above + BF3 reacting with NH3 + two other ones that weren't related to disadv of BL theory (think I was explaining how it was useful). You?

 

[dotwingz]

considering this is Board of Studies lol

This is a very important point. Sometimes people get too hung up based on what other people here are saying, this community probably relfects the upper bounds of the HSC cohort

 

[Idkwhattoput]

That’s easy 90 mate. Considering how usually 7% of the state gets a band 6 and most chemistry students don’t do higher level maths, also considering this is Board of Studies lol, you’ll get that band 6. I’m sure your top 7%

Honestly, that's why I felt the cutoff would be higher. I really just cannot see myself as a band 6 chem student. Phys, maths sure, but something about a band 6 in chem just seems unattainable. Especially given how bad my school is at chem

 

[worldno17]

Honestly, that's why I felt the cutoff would be higher. I really just cannot see myself as a band 6 chem student. Phys, maths sure, but something about a band 6 in chem just seems unattainable. Especially given how bad my school is at chem

nah man, don't overthink it. it's already done anyway!

 

[Arrowshaft]

not the person u quoted (but procrastinating on physics right now....) but I did the CaO reaction like the person above + BF3 reacting with NH3 + two other ones that weren't related to disadv of BL theory (think I was explaining how it was useful). You?

I didn’t have enough space to state the reactions so I just said AlCl3 and BF3 act as acids or something but don’t have a hydrogen atom so can’t be explained by BL theory. I just stopped at the minimum amount of equations they asked so I just included the ammonium chloride

 

[worldno17]

I didn’t have enough space to state the reactions so I just said AlCl3 and BF3 act as acids or something but don’t have a hydrogen atom so can’t be explained by BL theory. I just stopped at the minimum amount of equations they asked so I just included the ammonium chloride

yee it's fine. a chem teacher at my school just loves equations and said that there can never be too many haha. allg!

 

[englishessayssuck]

What reactions did you include?

like I used a lot of space to properly define the bronsted lowry theory (and all the acid and conjugate base stuff), had an example of both, used the NH4Cl as an example of a Bronsted Lowry reaction (which isn't arrhenius, thus generalising it) and also the disadvantages as per above (and of course the assessment statement)
used some extra booklets to fit stuff in lol

 

[Arrowshaft]

What HSC mark are we aiming for though?