A level chemistry help URGENT ‼️

Help… for the first page… most of the calculations for ph we don’t have to find a new volume and work that way but for the second page we do, why’s this?? How would I know tomorrow in the exam what to do

When do I know that I need to find new volume??

(edited 10 months ago)

Reply 1

_OSHii

bro i struggle with this too and nothings helping 😭
i’m going through machemguy but it’s not clicking. someone told me yesterday that the easiest way to do buffers is just learn the steps, there’s no point understanding it esp this late

Reply 2

_OSHii

oh wait i see it, on the first page the solutions all add to 1000cm3 so 1dm3 but on the second page they don’t do it’s got something to do with that. sorry i can’t help anymore than that 😭

Reply 3

Alevelhelp.1

Original post by _OSHii

oh wait i see it, on the first page the solutions all add to 1000cm3 so 1dm3 but on the second page they don’t do it’s got something to do with that. sorry i can’t help anymore than that 😭

You do ocr a right???
bro it’s defo on the exam tomorrow, and I bet it’s a chunky 7 marker 😭
If not that it’ll be worth more marks with parts a,b,c,d etc 😭
Good luck for the exam btw 🤍

(edited 10 months ago)

Reply 4

user8937264980

if youre working with an excess then you will need to put that excess over the total volume to find the concentration of the excess

Reply 5

Illumilottie

If there is a question where you are mixing two things, their concentrations will change

Find the new concentration of each species by doing old concentration x original volume/ new volume

Reply 6

_OSHii

Original post by Alevelhelp.1

You do ocr a right???
bro it’s defo on the exam tomorrow, and I bet it’s a chunky 7 marker 😭
If not that it’ll be worth more marks with parts a,b,c,d etc 😭
Good luck for the exam btw 🤍

yeah i do ocr 😭
i’m literally getting like in the 50s per paper and buffers transition and the electrode potentials is my downfall fr. Good luck to you too, looks like we’re gonna need it fr.
The machemguy explained buffers really well tbh, like you eventually end up getting it, also on pmt ocr recourses are so bad, if you go onto the aqa chem section and go on physical II they do model answers there on buffers and that really helped me understand the why a bit better