Hey there! Sign in to join this conversationNew here? Join for free
    Offline

    0
    ReputationRep:
    (Original post by INeedToRevise)
    differences have to be greater than 0.4V

    Can u help me


    pH of 0.015mol of acid is 1.82.

    Nitric acid is diluted with equal volume of water.

    How do you work out pH of diluted acid?
    I think that the moles would half as you are adding the exact amount of water so should be 0.0075 moles. - log(0.0075)=2.12
    Offline

    1
    ReputationRep:
    (Original post by sportycricketer)
    1. Buffers
    2. Transition Metals
    3. Rate Equation
    4. Born-Haber Cycle
    5. Electrode Potentials


    These are almost guaranteed to come up. They have tested Fuel Cells in both papers, I really hope they dont come up!
    but in biology I swear than innate behaviour stuff was tested in January and thats why i didnt revise it and then they put it in yesterday and ****ed my life over. LOL OCR are SOOOO SLY!

    ok maybe they didnt and i was imagining stuff lol
    Offline

    1
    ReputationRep:
    Given in on revision for tonight i think. Ill be cramming all tomorrow morning though
    Offline

    0
    ReputationRep:
    (Original post by voices1)
    its water. hAving said that, the conversations we had previously best to double check.
    What do you mean??
    Offline

    2
    ReputationRep:
    For Kstab you don't include H20 (on its own as a molecule) because it is in excess as all of the species are aqueous.
    Offline

    0
    ReputationRep:
    (Original post by susan23)
    but in biology I swear than innate behaviour stuff was tested in January and thats why i didnt revise it and then they put it in yesterday and ****ed my life over. LOL OCR are SOOOO SLY!

    ok maybe they didnt and i was imagining stuff lol
    haha yes indeed but that wasn't in the June paper though, that's all I'm saying lol. Hydrogen Future might creep up but having the fuel cell hatrick would be too much, no? lol
    Offline

    15
    ReputationRep:
    Good luck guys
    Offline

    1
    ReputationRep:
    Why is oxygen divided by four? What equation are they getting it from?

    Q7 a
    Attached Images
  1. File Type: pdf F325Jan11.pdf (206.7 KB, 79 views)
    Offline

    9
    ReputationRep:
    (Original post by susan23)
    but in biology I swear than innate behaviour stuff was tested in January and thats why i didnt revise it and then they put it in yesterday and ****ed my life over. LOL OCR are SOOOO SLY!

    ok maybe they didnt and i was imagining stuff lol
    whatever OCR does, EDEXCEL are still the professors in f***ing up people's whole summer holidays thinking about this f***ing stupid exams!!! I revised soo hard for this unit and then today I done the jan 11 paper and saw a question about hair and the R-S-S-R protein! WTF is that! I got 82 for that paper what is this in UMS?
    Offline

    1
    ReputationRep:
    (Original post by coffeestinks)
    why is oxygen divided by four? What equation are they getting it from?

    Q7 a
    yes thank you...im so confused on this too.
    Offline

    9
    ReputationRep:
    (Original post by CoffeeStinks)
    Why is oxygen divided by four? What equation are they getting it from?

    Q7 a
    yeah I wanna know that too I divided by 2 so scored only 1/4.
    Offline

    1
    ReputationRep:
    (Original post by Schoolio93)
    whatever OCR does, EDEXCEL are still the professors in f***ing up people's whole summer holidays thinking about this f***ing stupid exams!!! I revised soo hard for this unit and then today I done the jan 11 paper and saw a question about hair and the R-S-S-R protein! WTF is that! I got 82 for that paper what is this in UMS?
    LOOOL I know edexcel ****s everyone up iv had experience with them. and omg same!!!! wth was thaaaaaattt!! 82/100 is great! thats an A i think ...duno about ums...probably 120/150 no idea....dont count on it...could oyu help me with question 7 in the jan 2011 paper im so stuck!
    Offline

    1
    ReputationRep:
    (Original post by apo1324)
    For Kstab you don't include H20 (on its own as a molecule) because it is in excess as all of the species are aqueous.
    So if the equation was:

    Fe2+ + 6H2O --> [Fe(H2O)6]2+
    ( I don't know whether this is right )

    What would the Kstab be?
    Offline

    9
    ReputationRep:
    (Original post by susan23)
    LOOOL I know edexcel ****s everyone up iv had experience with them. and omg same!!!! wth was thaaaaaattt!! 82/100 is great! thats an A i think ...duno about ums...probably 120/150 no idea....dont count on it...could oyu help me with question 7 in the jan 2011 paper im so stuck!
    i'm sorry I scored 1/4 for that question coz I divided the whole thing by 2.
    Offline

    2
    ReputationRep:
    I hope this paper is harder than jan 11, low grade boundaries ftw
    Offline

    1
    ReputationRep:
    (Original post by Schoolio93)
    i'm sorry I scored 1/4 for that question coz I divided the whole thing by 2.
    same thats what i did....!
    Offline

    0
    ReputationRep:
    Revised my notes for chapter 1 and 2, just got half of chapter 3 to read over and done chapter 1 and 2 practice questions, just got to do the practice questions for chapter 3.

    Almost there now, feel as it should go okay providing there isn't any weird and wonderful questions on the paper. Either way I need a C or a D on this paper to get my A overall which should be achievable but I'd like to get an A on this paper really.

    Anyone got any ideas what the big essay questions worth a few marks could be on tomorrow? I know the obvious ones like buffers, transition metals, complex ions, electrochemical cells, hydrogen + fuels but does anyone have any more abstract ideas on what they could make into a long question.

    Good luck tomorrow everyone, at least we have the morning to get a final bit of revision done.
    Offline

    0
    ReputationRep:
    (Original post by Schoolio93)
    whatever OCR does, EDEXCEL are still the professors in f***ing up people's whole summer holidays thinking about this f***ing stupid exams!!! I revised soo hard for this unit and then today I done the jan 11 paper and saw a question about hair and the R-S-S-R protein! WTF is that! I got 82 for that paper what is this in UMS?
    Relax, that's a 150 UMS mark, as no one got above 80 in january.
    Offline

    0
    ReputationRep:
    Does anyone know if we have to know all the equations for car batteries, there is quite a big section in my textbook in the electrode potential chapter but it doesn't mention anything specific on the spec.
    Thanks
    Offline

    0
    ReputationRep:
    Listen, to the people who ask why you divide by 4 to get the DOC question on the jan. 11 paper:

    you work out the moles of thiosulfate ions they give you (conc. x volume) - those figures are given. Then you see that it's two moles thiosulfate to two moles of Iodide ions so their molar quantities are equal (this is looking at equation 3)

    Now look at equation 2: moles of Iodide ions are in equal ratio to Mn 3+ so moles of thiosulfate = moles of Mn 3+

    Look at equation 1: It's 4 moles of Mn 3+ to one mole 02 so divide that figure by 4

    Hope that helped you!
 
 
 
Poll
Do you agree with the PM's proposal to cut tuition fees for some courses?

The Student Room, Get Revising and Marked by Teachers are trading names of The Student Room Group Ltd.

Register Number: 04666380 (England and Wales), VAT No. 806 8067 22 Registered Office: International House, Queens Road, Brighton, BN1 3XE

Write a reply...
Reply
Hide
Reputation gems: You get these gems as you gain rep from other members for making good contributions and giving helpful advice.