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    (Original post by illusionz)
    You are correct.
    Fine. But there is another question about isotopes: Why it is possible that there are atoms which have more neutrons than protons in a nucleus? in other words: How isotopes come into being?
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    (Original post by D.Bman)
    Hi illusionz and Ari Ben Canaan, Thank you very much for your help indeed I really appreciated all the help you have given me

    Illusionz can i just have confirmation for Spectra number 1 and number 5 please ?
    Especially number 5 because I cant understand from the post weather it is an amine or amide ?
    And can you tell me what bonds might be present in this spectra ?
    Thank you very much Lads
    I think spectrum 1 is a hydrocarbon without a C=C, O, N etc It is possible there is a halogen but you really can't tell. You would need more data to determine the structure of the compound, NMR and mass spec would be very useful.

    As for 5, I do not think it is an amide as an amide C=O is generally ~1680 wavenumbers, and in any case, almost certainly below 1700. The C=O in this case is above 1700 which gives me the impression the C=O and N-H are seperate functional groups and not part of an amide.
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    (Original post by illusionz)
    I think spectrum 1 is a hydrocarbon without a C=C, O, N etc It is possible there is a halogen but you really can't tell. You would need more data to determine the structure of the compound, NMR and mass spec would be very useful.

    As for 5, I do not think it is an amide as an amide C=O is generally ~1680 wavenumbers, and in any case, almost certainly below 1700. The C=O in this case is above 1700 which gives me the impression the C=O and N-H are seperate functional groups and not part of an amide.
    Mate for number 1
    Can you tell me what would be reason for the hydrocarbon to not have the C=C and O, N having looked at the spectra ?
    Is it due to the peaks or something ?
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    (Original post by D.Bman)
    Mate for number 1
    Can you tell me what would be reason for the hydrocarbon to not have the C=C and O, N having looked at the spectra ?
    Is it due to the peaks or something ?
    Because the spectrum doesn't have peaks in the regions these bonds cause peaks to appear.
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    Hey Everyone
    Can someone help me with a chemistry question

    I need to draw just one mechanisms for

    Nitration of Benzene
    Ethane + Bromine
    Ethane + Chlorine

    Can someone help me draw these please

    Thank you everyone xx
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    (Original post by KellyRoth)
    Hey Everyone
    Can someone help me with a chemistry question

    I need to draw just one mechanisms for

    Nitration of Benzene
    Ethane + Bromine
    Ethane + Chlorine

    Can someone help me draw these please

    Thank you everyone xx
    For the nitration of benzene you are essentially reacting H2SO4 and HNO3 together to produce a Nitronium ion.

    Think about the interaction between the two acids.... Can you see a way by which a good leaving group (HINT: water) could be produced on the HNO3 molecule ?
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    (Original post by Ari Ben Canaan)
    For the nitration of benzene you are essentially reacting H2SO4 and HNO3 together to produce a Nitronium ion.

    Think about the interaction between the two acids.... Can you see a way by which a good leaving group (HINT: water) could be produced ?
    Right, So im essentially reacting :
    H2SO4 + HNO3 ----> Nitronium Ion ( Can you tell me the formula for this )

    So after reacting H2SO4 + HNO3 would i expect to see water being produced ?
    Can you correct me if am going wrong, because chemistry is my weakest subject
    Also what bonding would i see in this mechanism ? xx
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    (Original post by KellyRoth)
    Right, So im essentially reacting :
    H2SO4 + HNO3 ----> Nitronium Ion ( Can you tell me the formula for this )

    So after reacting H2SO4 + HNO3 would i expect to see water being produced ?
    Can you correct me if am going wrong, because chemistry is my weakest subject
    Also what bonding would i see in this mechanism ? xx
    Are you an A Level student ?

    I'm sure you are aware that the electrophile is NO2+ i.e. a nitronium ion.

    Essentially, what happens is that the Nitric acid takes a proton from the Sulphuric acid to produce a good leaving group (water).

    What is left is the NO2+ ion.

    What follows is your usual electrophilic aromatic substitution reaction.

    Here, have a look at this :

    Name:  mechanism.png
Views: 95
Size:  38.8 KB

    EDIT : The reaction equation is
    HNO3 + 2H2SO4 ---> 2HSO4- + NO2+ + H3O+
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    (Original post by Ari Ben Canaan)
    Are you an A Level student ?

    I'm sure you are aware that the electrophile is NO2+ i.e. a nitronium ion.

    Essentially, what happens is that the Nitric acid takes a proton from the Sulphuric acid to produce a good leaving group (water).

    What is left is the NO2+ ion.

    What follows is your usual electrophilic aromatic substitution reaction.

    Here, have a look at this :

    Name:  mechanism.png
Views: 95
Size:  38.8 KB

    EDIT : The reaction equation is
    HNO3 + 2H2SO4 ---> 2HSO4- + NO2+ + H3O+
    Ah I see, it now makes sense
    I understand now that you've added a diagram in, and i can understand whats going on the reaction
    And yes i am doing a levels, its just i find chemistry a bit tricky

    One thing I am confused about is what type of reaction is it ?
    Is it electrophilic aromatic substitution like you have stated above ?
    And what type of bonding is going on in this mechanism ?
    x
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    (Original post by KellyRoth)
    Ah I see, it now makes sense
    I understand now that you've added a diagram in, and i can understand whats going on the reaction
    And yes i am doing a levels, its just i find chemistry a bit tricky

    One thing I am confused about is what type of reaction is it ?
    Is it electrophilic aromatic substitution like you have stated above ?
    And what type of bonding is going on in this mechanism ?
    x
    The initial interaction between the two acids is a classic acid base reaction. Can you see how the Sulphuric acid donates a proton to the Nitric acid ? We then have a loss of water, which is secondary.

    What follows is an electrophilic aromatic substitution.

    Type of bonding ? What do you mean ?
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    (Original post by Ari Ben Canaan)
    The initial interaction between the two acids is a classic acid base reaction. Can you see how the Sulphuric acid donates a proton to the Nitric acid ? We then have a loss of water, which is secondary.

    What follows is an electrophilic aromatic substitution.

    Type of bonding ? What do you mean ?
    Oh Right, So we first have an acid base reaction with a proton being donated to the nitric acid. Then a loss of water occours, which is secondary. Then electrophilic subsitution.
    I understand it now

    Ben Canaan, I was asked in the question to analyse the type of reaction in each case in relation to its bonding.
    This is the part where i am confused on, Can you help me please ?
    x
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    I'm back!

    I have discussed the fusion between Uranium and Deuterium in the physics society. During the discussion I have read that Uranium and Deuterium applies an energy bonding to become to Plutonium. Why energy come into being during the bonding between Uranium and Deuterium? I suppose that Uranium and Deuterium have to get a stimulated state to come to a bonding, as atoms keep the low-energy state by nature. And when atoms attend a bonding, they are stimulated. That is my supposition.
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    Name: Aleisha Cullen
    Hobbies : singing, sport listening to music
    studying: AS chemistry, RS, psyschology and English literature
    live: westmiddlands
    why i like chemo: its logical and interesting
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    please help me with this question !!!

    Given that
    p(g) + 3Cl(g) = PCl3 (g) energy change = -983kjmol-1
    P(s) + 3/2Cl2(g) = PCl3(g) energy change = -305kjmol-1
    p(s) = p(g) energy change = +314kjmol-1

    Calculate the following bond energies:
    a) P-Cl in PCl3

    b) Cl-Cl in Cl2

    I really have no clue on how to do this so please help :s
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    (Original post by Aleisha1)
    please help me with this question !!!

    Given that
    p(g) + 3Cl(g) = PCl3 (g) energy change = -983kjmol-1
    P(s) + 3/2Cl2(g) = PCl3(g) energy change = -305kjmol-1
    p(s) = p(g) energy change = +314kjmol-1

    Calculate the following bond energies:
    a) P-Cl in PCl3

    b) Cl-Cl in Cl2

    I really have no clue on how to do this so please help :s
    Hint : Enthalpy change of reaction = Energy used to Break bonds - Energy used to form bonds.
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    (Original post by Ari Ben Canaan)
    Hint : Enthalpy change of reaction = Energy used to Break bonds - Energy used to form bonds.
    I dont understand why enthalpy change = bonds broken - bonds formed


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    hi could anyone give me some advice? Basically I am considering being a pharmacist but I don't know that much about it. What different things can a pharmacist do?
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    (Original post by tree123)
    hi could anyone give me some advice? Basically I am considering being a pharmacist but I don't know that much about it. What different things can a pharmacist do?
    Hey! You'd probably be better suited to looking around in and maybe starting a thread in this forum. You're more likely to get an informed reply there.
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    (Original post by Loz17)
    Hey! You'd probably be better suited to looking around in and maybe starting a thread in this forum. You're more likely to get an informed reply there.
    thankyouu! I was trying to find the right place to post it!
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    (Original post by Loz17)
    Hey! You'd probably be better suited to looking around in and maybe starting a thread in this forum. You're more likely to get an informed reply there.
    do you know what jobs I could go into with a chemistry degree?:P

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