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Chemistry: Post your doubts here!

Discussion in 'International A And AS Level' started by XPFMember, Sep 29, 2011.

  1. Hikaze123

    Hikaze123

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    K Thx!
     
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  3. Hamnah Zahoor

    Hamnah Zahoor

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    For Question 23

    Minimum number of carbon required for isomerism is 4..less than this isomerism can not be done thus, each product having equal carbon will have 4 carbons leading to N=8 so when 8/2=4 carbon each

    for question 24

    i don't understand it much but from seeing the option C...addition of steam and Conc.H2SO4 leads to removal of the double bond and water being added at the point
    the -OH attached is secondary alchohal for it being attached to carbon that has two carbons attached.further on addition of hot acidified KMnO4 it oxidises the secondary alchohal group to ketone and the primary alcohals on each side to carboxylic acid.....You will understand it much better when you draw displayed formulas of the compond given.
     
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  4. Hikaze123

    Hikaze123

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    Thanks for your help again!!!
     
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  5. Unknown202

    Unknown202

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  6. Unknown202

    Unknown202

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    i need a help in this question why is it A?
     
  7. studyingrobot457

    studyingrobot457

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    no image
     
  8. Unknown202

    Unknown202

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  9. Unknown202

    Unknown202

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    Now ?!
     
  10. Hamnah Zahoor

    Hamnah Zahoor

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    When ever two stages are involved in reaction its ethalpy profile diagram will have two humps in its graph .......as it is stated in the question X-Y is positive thus it will be endo and reactants will have low energy than the products....in Y-Z ethalpy change is neg thus its exo and reactants will have high energy than products as shown in option A
     
  11. Unknown202

    Unknown202

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    So it can't be B r8
     
  12. Hamnah Zahoor

    Hamnah Zahoor

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    No....no humps in the graph
     
  13. Unknown202

    Unknown202

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    K thx soo much:LOL::)
     
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  14. MShaheerUddin

    MShaheerUddin

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  15. sweetiepie94

    sweetiepie94

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  16. MnMz Mohammad-M

    MnMz Mohammad-M

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    The balanced equation should be 10Al + 3Ba(NO3)2 = 5Al2O3 + 3BaO + 3N2 , right? therefore we will get a different answer..
    plz reply as soon as possible..
     
  17. Tigercub

    Tigercub

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    Can anyone help me please?
    What is involved in the mechanism of the mechanism of the reaction between aqueous sodium hydroxide and 2-bromo-2-methylbutane?
    A heterolytic bond fission, attack by an electrophile on a carbanion
    B heterolytic bond fission, attack by an nucleophile on a carbocation
    C homolytic bond fission, attack by an electrophile on a carbanion
    D homolytic bond fission, attack by an nucleophile on a carbocation
     
  18. Metanoia

    Metanoia

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    2-bromo-2-methylbutane is a tertiary halogenoalkane and will undergo sN1 'unimolecular' via carbocation reactions.

    [​IMG]

    The C-Br bond will be broken heterolytically and a carbocation ion will be formed. The carbocation would then be attacked by the nucleophile (OH-)
     
  19. Metanoia

    Metanoia

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    I don't have the context of the full question.

    But in both equations, the ratio of Ba(NO3)2 and N2 happens to be 1:1. Therefore, it's a coincidence that the answers ended up to be the same.
     
  20. MShaheerUddin

    MShaheerUddin

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    Can you answer my question please?
     
  21. fahadhameedahmad

    fahadhameedahmad

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    are you talking about this question
     

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