Im not sure but i think you have made a mistake in the calculation of moles of OH-. Seems to be out by a factor of 10 which would make the answer 12.63 instead of 11.63
Hi, thank you very much as you predicted this came up. But I am really stressing right now since I have done the curve starting from ACID ph then finished at alkali pH as required but I never drew a curve it was more like 3 straight lines. So I went with a ruler till equivalence point then drew another straight line till final pH. Will I get penalised?
@@lumiinouss4744 I feel so guilty 😢 I am such an idiot literally never thought about the curve even though it clearly says 'curve'? Also do you remember if the first question said state the block and explain why? I literally just said 'block s' and never gave an explanation for it.
@@FR-tn4qj i also made a silly mistake converting 0.037g into mg :( instead of multiplying by 1000 i divided by 1000 like an idiot (oh and your right someon just told me)
You are so helpful. I literally watched this 5 minutes before my OCR paper today, and it came up. Thanks so much!
Hi, do you happen to have a quick revision video on structure of graphite, diamond etc. Like their MP.
hi sir,
for Q1)E), how do you know that doubling the concentration will half the equivalence point? thank you!!
Just think about any acid-alkali titration. If you doubled the concentration of the acid in the burette, the titre would half
@@MaChemGuy thanks! :)
why didn't you subtract the moles of KOH with CH3COOH if the KOH is in excess?
for the second question, how do u know where to draw the equivalence point exactly at like which pH u start?
It doesn't matter, just make sure that it is above pH 7 (as it's a weak acid/strong base combo, SA/WB's equivalence point is below pH 7)
for q2 - it doesnt mention the temp being 25c so can we assume kw is 1x 10-14 if the question doesnt mention the conditions
You’d have to yes. I took this directly from a paper so that’s how it appeared
In the a level exams, would you recommend doing the multiple choice questions first or last? And how much time time should I spend on the them?
I recommend my students to do them last. Leave around 25-30 mins.
Ok, thank you!
Im not sure but i think you have made a mistake in the calculation of moles of OH-. Seems to be out by a factor of 10 which would make the answer 12.63 instead of 11.63
nar mate
@@hk4560 don’t matter for me anymore mate
Hi, thank you very much as you predicted this came up. But I am really stressing right now since I have done the curve starting from ACID ph then finished at alkali pH as required but I never drew a curve it was more like 3 straight lines. So I went with a ruler till equivalence point then drew another straight line till final pH. Will I get penalised?
unfortunately it will because its not supposed to be straight lines, but if you got the correct alkali Ph and correct H+ Ph you should get 2/3 marks
@@lumiinouss4744 I feel so guilty 😢 I am such an idiot literally never thought about the curve even though it clearly says 'curve'? Also do you remember if the first question said state the block and explain why? I literally just said 'block s' and never gave an explanation for it.
@@FR-tn4qj wait it didnt say explain? i dont remeber seeing explain ..
@@FR-tn4qj i also made a silly mistake converting 0.037g into mg :( instead of multiplying by 1000 i divided by 1000 like an idiot
(oh and your right someon just told me)
@@lumiinouss4744 this is bad literally one mark down the drain I never read 'explain'
hi there, just wondering if the AS 2019 exam papers are available to you?
Livya Xx Sorry but I’m not allowed to share. Can’t you badger your teacher??
@@MaChemGuy Yes I will drop her an email again if it is already out as I emailed her on Thursday and she told me it was not available yet.
Livya Xx If your school/college doesn’t do AS it’s not available till August.
@@MaChemGuy oh right! That sucks. Thanks for letting me know sir
Which exam board do you teach?
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