Join TSR now and get all your revision questions answeredSign up now

ocr f332 mole ratio Watch

    • Thread Starter
    Offline

    0
    ReputationRep:
    http://www.ocr.org.uk/download/pp_11...n_gce_f332.pdf

    3a.

    I got the moles of each, now what? I don't really understand what the markscheme says..

    Thanks

    Also, for 1g in making propene into a bromoalkane, why is uv radiation necessary? i thought you just neded the aqeous solution of chlorine (hcl) in a seperating funnel, decanting the upper layer off, shaking with sodium hydrogencarbonate, adding anyhdrous sodium sulfate and distilling for purity? none of this was in the mark scheme, but uv radiation and chlorine was...
    • Thread Starter
    Offline

    0
    ReputationRep:
    in fact upon counting, propene to compound a means HCL was used, due to an extra hydrogen atom, therefore it must have been HCL.. why does the mark scheme say chlorine and UV?or have i gone wrong?
    Offline

    0
    ReputationRep:
    Mr KCl= 74.6 Mr NaCl = 58.5

    in 100g,

    KCl = (1/3)100g NaCl = (2/3)100g

    this in moles is

    KCl = 100/(3*74.6) NaCl = 200/(3*58.5)

    in terms of K and Na is the same cause there is one mole of each in the corresponding compounds

    so K:Na = 100/(3*74.6) : 200/(3*58.5)


    ok im gonna edit this cause it might look confusing:

    for every 1 gram of KCl there will be 2 grams of NaCl (because its two thirds is twice as much as one third)

    so this in moles will be

    (moles of kcl) 1/74.6 (moles of nacl) 2/58.5

    1 mole nacl has 1 mole na, 1 mole kcl has 1 mole k
    so the ratio for k:na doesnt change
    Offline

    0
    ReputationRep:
    for 1g

    the reaction is propane -> chloropropane

    this can happen as a photochemical reaction with chlorine
 
 
 
Poll
How are you feeling about Results Day?

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

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