Turn on thread page Beta

OCR Chemistry F321 22nd June 2015 *OFFICIAL THREAD* watch

    • Thread Starter
    Offline

    3
    ReputationRep:
    Hey guys i thought I would make a thread for those taking the F321 exam this Friday! Any tips? Also does anyone have predictions for the 5/6 mark questions at the end?

    Good luck!
    Offline

    2
    ReputationRep:
    All I was doing is just doing past papers and learning mark schemes for similar questions. I think this year the paper might be a weird one, as last year it was also sort of weird. The 5 or 6 mark question will probably be something on bonding or group 7 reactivity or something similar
    Hows your revision going anyway?
    Offline

    3
    ReputationRep:
    Has anyone got any practice questions apart from the actual past papers??
    Offline

    2
    ReputationRep:
    Could someone please explain the reactivity trend down group 7 and group 2???
    Offline

    0
    ReputationRep:
    (Original post by pauux)
    Could someone please explain the reactivity trend down group 7 and group 2???
    Group 2:
    To react, a group 2 element has to lose electrons

    Reactivity increases down the column as the atom size increases due to increasing number of shells which therefore means that it's easier for an atom to lose an electron and react TL;DR electrons further from the nucleus, easier to lose

    Group 7:
    To react, a group 7 element has to attract electrons

    Reactivity decreases down the column as the outer shell is further away from the nucleus. It is harder for the nucleus to attract an electron because of the increasing distance. TL;DR electrons further away from the nucleus, harder to attract
    Offline

    7
    ReputationRep:
    (Original post by pauux)
    Could someone please explain the reactivity trend down group 7 and group 2???
    Group 2
    -reactivity increases as you go down
    -as you go down, number of shells increases
    -therefore atomic radius and electron shielding increases
    -therefore weaker force of nuclear attraction on the outer electron
    -means that outer electron is easier to lose, and group 2 elements react via losing outer electrons

    Group 7
    -reactivity decreases as you go down
    -same factors as group 2 metals
    -group 7 halogens react by gaining electrons, but as there is more shielding and less nuclear attraction on the outer electrons the further you go down, electrons are harder to gain, so are less reactive

    Basically the same explanation, but they react in different ways, leading to different reactivity trends. Also, as a sidenote, the number of protons in the nucleus does increase as you go down the group, but this has little effect compared to electron shielding and atomic radius effect.

    Hope this helped
    Offline

    2
    ReputationRep:
    (Original post by maxAmain)
    Group 2:
    To react, a group 2 element has to lose electrons

    Reactivity increases down the column as the atom size increases due to increasing number of shells which therefore means that it's easier for an atom to lose an electron and react TL;DR electrons further from the nucleus, easier to lose

    Group 7:
    To react, a group 7 element has to attract electrons

    Reactivity decreases down the column as the outer shell is further away from the nucleus. It is harder for the nucleus to attract an electron because of the increasing distance. TL;DR electrons further away from the nucleus, harder to attract
    (Original post by lukejoshjames)
    Group 2
    -reactivity increases as you go down
    -as you go down, number of shells increases
    -therefore atomic radius and electron shielding increases
    -therefore weaker force of nuclear attraction on the outer electron
    -means that outer electron is easier to lose, and group 2 elements react via losing outer electrons

    Group 7
    -reactivity decreases as you go down
    -same factors as group 2 metals
    -group 7 halogens react by gaining electrons, but as there is more shielding and less nuclear attraction on the outer electrons the further you go down, electrons are harder to gain, so are less reactive

    Basically the same explanation, but they react in different ways, leading to different reactivity trends. Also, as a sidenote, the number of protons in the nucleus does increase as you go down the group, but this has little effect compared to electron shielding and atomic radius effect.

    Hope this helped
    Thanks so muchh xx Very helpful !!
    Offline

    0
    ReputationRep:
    (Original post by TSR121)
    Hey guys i thought I would make a thread for those taking the F321 exam this Friday! Any tips? Also does anyone have predictions for the 5/6 mark questions at the end?

    Good luck!
    Pretty sure this Friday is still May
    Offline

    0
    ReputationRep:
    any key topics anyone thinks is likely to come up and worth revising?
    Offline

    7
    ReputationRep:
    (Original post by pauux)
    Thanks so muchh xx Very helpful !!
    No problem, if there's anything else you need help with just ask.
    Offline

    7
    ReputationRep:
    (Original post by Aaron Walker)
    any key topics anyone thinks is likely to come up and worth revising?
    Bond angles and the halogen reactions come up frequently, as well as group and period trends. They all seem to be worth a good amount of marks in the exams so are worth revising.
    Offline

    10
    ReputationRep:
    Hi, could someone help?
    How does the ease of thermal decomposition change as you go down group 2?
    Thanks!


    Posted from TSR Mobile
    Offline

    2
    ReputationRep:
    I've done 2 past papers for chemistry in the past 24 hours and achieved 60/60 marks for both of them. I marked the first one by myself and my chemistry teacher marked my second one (as well as checking over the first one I marked myself).

    Feeling really confident for the chemistry exams this year.
    Offline

    10
    ReputationRep:
    Also, does anyone have last years f321 paper? Are we allowed access to it yet?


    Posted from TSR Mobile
    Offline

    0
    ReputationRep:
    (Original post by TheDaniel)
    I've done 2 past papers for chemistry in the past 24 hours and achieved 60/60 marks for both of them. I marked the first one by myself and my chemistry teacher marked my second one (as well as checking over the first one I marked myself).

    Feeling really confident for the chemistry exas this year.
    get you
    Offline

    7
    ReputationRep:
    (Original post by Pumuki63)
    Also, does anyone have last years f321 paper? Are we allowed access to it yet?


    Posted from TSR Mobile
    This was posted on another thread.
    Attached Images
  1. File Type: pdf f321_ms_jun14.pdf (326.5 KB, 2087 views)
  2. File Type: pdf F321-01-Jun14.pdf (476.7 KB, 669 views)
    Offline

    2
    ReputationRep:
    (Original post by Aaron Walker)
    get you
    Got me.
    Offline

    1
    ReputationRep:
    Quick question: when talking about the symmetry of molecules (usually in the context of why X is non-polar), would CH4 be considered symmetric but CH3Cl be considered asymmetric , or is it to do with the shape of the actual molecule e.g. trigonal planar or tetrahedral? Pretty sure the first is correct but just wanted to check!
    Offline

    4
    ReputationRep:
    Well good luck all for Friday. I'm going to do 2 past papers tomorrow when I get back from college and I'll probably leave it at that.

    Cant wait to drop chemistry.
    Offline

    15
    ReputationRep:
    Guys be ready i do OCR physics and the exam was nothing like the past papers it was totally opposite, i know this is chemistry but its OCR i dont trust them. In our exam no definitions came up, we had to explain a term which i dont think is in our spec
 
 
 
Reply
Submit reply
Turn on thread page Beta
Updated: May 28, 2016

University open days

  1. University of Cambridge
    Christ's College Undergraduate
    Wed, 26 Sep '18
  2. Norwich University of the Arts
    Undergraduate Open Days Undergraduate
    Fri, 28 Sep '18
  3. Edge Hill University
    Faculty of Health and Social Care Undergraduate
    Sat, 29 Sep '18
Poll
Which accompaniment is best?

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.