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    I was resitting and dont think the paper was that great
    I think I've got the bond enthalpy question wrong, put -198
    And I got the whole bond angle one wrong
    As the answer is predicted 109 and actually 60!
    Oh well! Hopefully scrape an A
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    (Original post by Bennyh2k9)
    I made 1 definite silly mistake and it was accidently doing a covalent dot and cross diagram instead of ionic
    What mistakes have you made?
    Made the same mistake
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    (Original post by shooting_stars)
    Made the same mistake
    Same

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    (Original post by Elhamm)
    LOL Well that's why we're so precious :P Haha Bless her though
    Shes only 4.. soo cute!! How does people call you? Most call her Ellen, some eLHHam, some elhaN lol

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    (Original post by tealover96)
    I was resitting and dont think the paper was that great
    I think I've got the bind enthalpy question wrong, put -198
    And I got the whole body angle one wrong
    As the answer is predicted 109 and actually 60!
    Oh well! Hopefully scrape an A
    How do u know its 60



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    (Original post by f.loco)
    How do u know its 60



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    Search it on google.. the bond angle of cyclopropane.. 60 comes up
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    (Original post by shooting_stars)
    Search it on google.. the bond angle of cyclopropane.. 60 comes up
    Daaam ur right. I put its gonna be smaller so about 104° its wrong i know but i explained it as 'as in corners of triangle, electron densities is squashed' do i get mark for explanation

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    (Original post by f.loco)
    Daaam ur right. I put its gonna be smaller so about 104° its wrong i know but i explained it as 'as in corners of triangle, electron densities is squashed' do i get mark for explanation

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    Hmmm cuz it's Salters im not so sure.. I think the explanation is dependant on the right bond angle
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    (Original post by shooting_stars)
    Search it on google.. the bond angle of cyclopropane.. 60 comes up
    Ahh i put 106 -.- I dont think I put the right answer
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    (Original post by m.chloe)
    for the second stage my mind went completely blank...but I put 'electric field, ions have same kinetic energy'...completely forgot about acceleration..would I still get the mark? :/
    Maybe, you might have to mention acceleration
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    For that bond angle one, you didn't have to state the actual angle, it only said state how it differs
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    (Original post by fudgeboy989)
    Same here. I know silicate would have oxygen, but I thought the question said silicide?


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    Anything ending in -ate means there is an oxygen in the compound. Silicate, chlorate etc

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    Need to ask a few q's real quick:
    For the bond angles q, I know I got both the angles wrong, but would I get two or one mark/s for saying
    -electrons repel
    -in order to minimise repulsion
    Bc in ALL the past paper q's I've seen, they credit marks for those two answers, and usually one for the bond angle (in this case it would be 2 I assume).
    In the Mendeelev question, I wrote that he guessed the elements would be there because he left gaps in the table and assumed the new element would follow existing trends in the group (didn't use keywork, properties, I think).
    For the gas volume q, I only worked out the moles of the hydrogen peroxide, even though it asked for steam and whatnot, would I get method marks for working out the moles for H2o2 and then times 70? Even though I didn't do it for all the reagents?

    Final one- For the emission q,
    I wrote when electrons gain energy they move up and down energy levels (missed out keyword-excited)
    When they do down energy levels they emit electromagnetic radiation(energy) in the form of photons, the energy released is proportional to a specific frequency, (same thing as stating equation), and the gaps between lines, and energy levels are unique for specific elements. Did anyone else get that?
    Also, I lost one mark for the formation q, as I wrote the equation and the symbols but I didn't balance it, do I still get a mark?
    I pray we all do well IA
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    wouldn't it have to be a positive enthalpy change of reaction considering it was used in rockets??? i could be wrong but i was just thinking...
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    (Original post by DominoMatrix227)
    Me too, were you supposed to explain why or state that it speeds up the rxn? I didn't
    the zeolite acts as a molecular sieve, allowing straight chain molecules to pass through but trap branched chains, this allows for separation of the products during cracking
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    (Original post by 9589)
    the zeolite acts as a molecular sieve, allowing straight chain molecules to pass through but trap branched chains, this allows for separation of the products during cracking
    That's not cracking that's isomerisation.

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    (Original post by TheGreatImposter)
    That's not cracking that's isomerisation.

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    surely it can work in that way for both?
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    (Original post by 9589)
    surely it can work in that way for both?
    No cause in cracking branched chains are not formed only smaller hydrocarbons and alkenes are

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    is there an unofficial mark scheme for this yet??
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    (Original post by TheGreatImposter)
    No cause in cracking branched chains are not formed only smaller hydrocarbons and alkenes are

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    Actually the chemical storylines book says that branched alkanes can be produced in cracking, but I'm still sure they'll prob reject the answer anyway
 
 
 
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