HSC Chemistry SOLUTIONS / Thoughts / Predictions (1 Viewer)

Speed’o’sound Sonic

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DARN IT! I would've gotten it too. I was thinking of using Ksp, but I brushed it aside because it didn't say 25 C. Welp.
That one was probably the toughest question IMO, took me a while to recognise to use the Ksp and to just kinda ignore the H+ present
 

donutsausage

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hope so haha
It was 10g of NaOH. 10g/(40g/mol) = 0.25 mol, whereas HCl was 100mL at 2M=0.2 mol so HCl was limiting reagent. I don't think it actually matters for your temp since either way only 0.2mol of water is neutralised but maybe they'll dock a mark for wrong limiting reagent.
 

osnola

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does anyone know how many marks question 31 was worth? the one with finding the concentration of chloride ions in the solution with silver
 

Speed’o’sound Sonic

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It was 10g of NaOH. 10g/(40g/mol) = 0.25 mol, whereas HCl was 100mL at 2M=0.2 mol so HCl was limiting reagent. I don't think it actually matters for your temp since either way only 0.2mol of water is neutralised but maybe they'll dock a mark for wrong limiting reagent.
Yeah I’ll lose a mark because I ignored the energy emitted as the other 0.05 mol of NaOH dissociated.
Other than that I’m g I think
 

JeydinNewWon

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Yeah I’ll lose a mark because I ignored the energy emitted as the other 0.05 mol of NaOH dissociated.
Other than that I’m g I think

I'm an idiot and used the 0.05 mol excess to calculate energy. SO I literally times the 0.05 to the NaOH molar enthalpy of combustion. I feel so stupid... Might just lose one mark but my process otherwise was correct.
 

Speed’o’sound Sonic

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I'm an idiot and used the 0.05 mol excess to calculate energy. SO I literally times the 0.05 to the NaOH molar enthalpy of combustion. I feel so stupid... Might just lose one mark but my process otherwise was correct.
I imagine you’ll only lose 1 mark overall out of the 4-odd for the question
 

JeydinNewWon

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That one was probably the toughest question IMO, took me a while to recognise to use the Ksp and to just kinda ignore the H+ present
Also, for the assumption of 25*C thing, I mean it feels like a "spherical cow" issue. It does feel a bit weird just to do that...I felt they really should have specified. But oh well, 4 marks just deleted like that :)))))))
 

Speed’o’sound Sonic

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Also, for the assumption of 25*C thing, I mean it feels like a "spherical cow" issue. It does feel a bit weird just to do that...I felt they really should have specified. But oh well, 4 marks just deleted like that :)))))))
As long as you got something relevant on the page I imagine you’ll get 1 or 2 maybe. Wouldn’t write off all 4 straight away. Still, I think its safe to assume but idk how they’ll mark it
 

JeydinNewWon

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Okay sorry for the wait I’m back will be done within the hour most likely
Hey I never really got to talk to you, personally because I was a lurker...but I just wanted to thank you deep down because of your effort for Chemistry. Thanks for taking the time to tutor students and have time to help out on BoredOfStudies. Really means a lot and I appreciate your work.
 

jazz519

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Hey I never really got to talk to you, personally because I was a lurker...but I just wanted to thank you deep down because of your effort for Chemistry. Thanks for taking the time to tutor students and have time to help out on BoredOfStudies. Really means a lot and I appreciate your work.
No worries thank you for the kind words :)
 

Esdog07

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I don't know why but after I completed question 30 in that exam, I got a confidence boost??
 

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