Speed’o’sound Sonic
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- 2020
I think unless specified otherwise you can assume it’s 25*CYou know, PEAK used KSP for the CaOH question...but it didn't specify the temperature was at 25C.
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I think unless specified otherwise you can assume it’s 25*CYou know, PEAK used KSP for the CaOH question...but it didn't specify the temperature was at 25C.
I think unless specified otherwise you can assume it’s 25*C
hope so hahaAlso I’m fairly certain their final q solution is wrong as NaOH was the limiting Reagent and not HCl
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+ presentDARN 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.
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.hope so haha
3 I thinkdoes anyone know how many marks question 31 was worth? the one with finding the concentration of chloride ions in the solution with silver
Yeah I’ll lose a mark because I ignored the energy emitted as the other 0.05 mol of NaOH dissociated.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
I imagine you’ll only lose 1 mark overall out of the 4-odd for the questionI'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.
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 thatThat 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
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 itAlso, 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))))))
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.Okay sorry for the wait I’m back will be done within the hour most likely
No worries thank you for the kind wordsHey 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.
Hey, could you send me the paper pls? I'd like to have a lookOkay sorry for the wait I’m back will be done within the hour most likely
Hi got the paper off someone and I don't have permission from them to share it, so unfortunately I cantHey, could you send me the paper pls? I'd like to have a look
