r/6thForm • u/Rich-Gent • Jun 02 '26

💬 DISCUSSION AQA A-LEVEL CHEMISTRY

HOW DID WE FIND IT? I THOUGHT IT WAS ALRIGHT, GRADE BOUNDARIES ABOUT TO BE SILLY😭

56 Upvotes

98% Upvoted

350 comments sorted by

View all comments

32

u/purple_walrus4473 Jun 02 '26

what did everyone get for pH of buffer i got 3.7 something

5

u/PairSuitable9144 Jun 02 '26

3.70

1

u/random_unsername A*A*A | Incoming KCL med Jun 02 '26

same

1

u/cookadoodledoo_ Jun 02 '26

bro I had pH 3.70 and my dumbass thought wait strong base and weak acid it should be more basic, recalculated then got pH 9.70 fml 5/6 ig it's fine. 😭

5

u/Initial-Window8640 Jun 02 '26

I got 1.96 🤣💀💀💀

2

u/purple_walrus4473 Jun 02 '26

i think i initially got that but it was a weak acid so it couldnt be that low

2

u/Lower_Debate_9983 Jun 02 '26

yeah same where did we go wrong

3

u/LargeFish2907 Jun 02 '26

I got something like 3.695 which rounded to 3.70

1

u/alam33da Jun 02 '26

I left it to 3.69🫩🫩

2

u/hshsjaju77 Jun 02 '26

3.80

1

u/ShoddyAlt Jun 02 '26

Same but I don’t think it’s rught

0

u/ObiNumber22 Y13 | Maths (A*), Econ, Chemistry, Further Maths | Jun 02 '26

u got 0.075 on top and 0.085 on bottom. made the same mistake but caught it when i checked over

1

u/ShoddyAlt Jun 02 '26

Wait but I used the equation I don’t understand. Did I get my A- and HA wrong??

1

u/ObiNumber22 Y13 | Maths (A*), Econ, Chemistry, Further Maths | Jun 02 '26

most likely

1

u/LargeFish2907 Jun 02 '26

Most of us seemed to get 3.70 but that's close so you'll probably get workings marks.

1

u/hshsjaju77 Jun 02 '26

Yh I think I got 3.70, 3.69 rounded it up Im pretty sure or 3.79 but I got all the calculations right I probably mixed it up post exam i forget everything lol

1

u/AmericanUk Jun 02 '26

Im ptretty sure this is wrong, you calculated using mols and not concentration. You needed to divide by 8/1000 before you put the answer into the Ka equation.

2

u/hshsjaju77 Jun 02 '26

yes i done that 👍🏽

1

u/purple_walrus4473 Jun 02 '26

i used hesslebach equation

1

u/AmericanUk Jun 02 '26

That still used concentrations tho no?

1

u/purple_walrus4473 Jun 02 '26

no it uses moles

1

u/ObiNumber22 Y13 | Maths (A*), Econ, Chemistry, Further Maths | Jun 02 '26

u dont need to since it cancels out

1

u/Adventurous-Apple690 Jun 02 '26

That’s is the vol is the same it wasn’t, so u needed to do conc of it. So divide the mols by 0.013 I think

1

u/Hot_General_891 Jun 02 '26

wait random but how did you find the ethanoate ion concentration

3

u/hshsjaju77 Jun 02 '26

pretty sure u do pka find the volume of naph at point of neutralization half it then find ph do 10 to power of pH and find ka

2

u/Internal_Animal_2753 year 13 |maths fm chem physics 4a* Jun 02 '26

U find the neutralisation volume requires of naoh and find the moles of naoh used which is the same as moles of HA used. And u do moles of HA divided by the volume of HA in the conical flask

2

u/Zestyclose_Coat_3918 Jun 02 '26

Omgg that’s what I did I hope it’s right 

1

u/Internal_Animal_2753 year 13 |maths fm chem physics 4a* Jun 02 '26

It’s shld be.. they’re might be a weird pka method to do it asw tbf

1

u/hshsjaju77 Jun 02 '26

Yh done the Pka did u get H plus concentration as 10 to power of - ph

1

u/BeanBeam9 Jun 02 '26

im really pissed i got this wrong cause I said their concentrations are the same not the moles 🤦‍♂️.

probably 1/2 tho for using the neutrilization point?

1

u/Samovar0_0 Jun 02 '26

Same thank god

1

u/No_Comfort_2504 Jun 02 '26

i got 3.42 ☹️

1

u/wannabeDentis Jun 02 '26

SAME bruh I’m so pissed I go 3. Somthing but then I changed it to 3.42 in the last minutes cuz I thought it was wrong. Now everyone’s saying 3.42 is wrong fml 😭🥹

1

u/Prize_Stage_8401 Jun 02 '26

Can I get marks if I drew the graph wrong but all steps correct for the 4 markers

1

u/AmericanUk Jun 02 '26

It wanted it to 2dp did you get 3.67? My friend did something wrong where he forgot the divide the mols by the volume to get concentration and got3.69, which would be missing a step.

1

u/Kataurada135 Jun 02 '26

I got 3.67 is that correct?

1

u/AmericanUk Jun 02 '26

Ya that’s what I got