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    Need help to find the structural formula of the skeletal structure above. There are two lines on carbon 3.
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    (Original post by Habeeb H Patel)
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    Need help to find the structural formula of the skeletal structure above. There are two lines on carbon 3.
    cant really see what you mean
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    (Original post by Habeeb H Patel)
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    Need help to find the structural formula of the skeletal structure above. There are two lines on carbon 3.
    so structural formula is CH3CH2C(CH2)CH2CH2CH3
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    (Original post by dip0)
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    so structural formula is CH3CH2C(CH2)CH2CH2CH3
    Thank you, so the name is 3-methylpentan-3-ene
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    (Original post by Habeeb H Patel)
    Thank you, so the name is 3-methylpentan-3-ene
    The IUPAC name is 2-ethyl pent-1-ene

    the longest carbon chain length that includes the double bond is 5 carbons long and the double bond is at carbon 1 (always use the lower number so don't use carbon 2) hence pent-1-ene

    the ethyl group is at carbon 2 hence 2-ethyl pent-1-ene
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    (Original post by dip0)
    The IUPAC name is 2-ethyl pent-1-ene

    the longest carbon chain length that includes the double bond is 5 carbons long and the double bond is at carbon 1 (always use the lower number so don't use carbon 2) hence pent-1-ene

    the ethyl group is at carbon 2 hence 2-ethyl pent-1-ene

    Why isnt it the six carbon atoms in a row, so shouldnt it be hexene except for pentene.
    Also if you dont mind, whats the purpose of Enthaply of atomization. Why do you have to convert the element in its standard state like sodium to gaseous state.What is the point of turning it into gas? Would be grateful if you do choose to answer
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    (Original post by Habeeb H Patel)
    Why isnt it the six carbon atoms in a row, so shouldnt it be hexene except for pentene.
    Also if you dont mind, whats the purpose of Enthaply of atomization. Why do you have to convert the element in its standard state like sodium to gaseous state.What is the point of turning it into gas? Would be grateful if you do choose to answer
    it would be 3-methyl HEXene if the double bond didn't exist at carbon-3. The double bond exists and so it takes priority in the nomenclature (as the double bond is a functional group). So therefore we have to count the longest carbon chain with respect to the double bond. (i.e. count the longest carbon chain which includes the double bond).



    As with enthalpy of atomisation, lets use the example of Na + F.
    2Na + F2 -> 2NaF
    we also know that NaF has ionic bonding and this can only happen if we have Na+ and F- ion

    We need to think of a way to convert sodium metal (which has metallic bonding) and flourine gas (which is diatomic) to the above species to form the ionic bonds.

    How to convert sodium metal to Na+? We know that in sodium metal (solid state) the Na+ ions have delocalised electrons. and the ions are packed together. So convert the sodium ions in solid state to sodium atom in gaseous state. We dont have the Na+ yet..
    The same is true for F2. Convert the diatomic molecule to form isolated F atoms. We dont have F- ions yet...

    So now we can easily have Na to Na+, and F to F-. Just transwer the 3s electron from Na to F. (This process has to be done in gaseous state in the born haber cycle as isolated species can only exist in a gas state, you can imagine transferring the electron from sodium to flourine is much easier if we had Na atoms isolated from each other (in a gas state) than thaving lots of Na+ ions packed together in a solid state)

    Think of a mechanism ( = everything mentioned above) to convert Na(s) + F2(g) -> NaF(s)
    This should help you to understand the purpose of enthalpy of atomisation in the process of forming ionic species and why it occurs in gas state.
 
 
 
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