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    Are my definitions right? i keep getting different definitions from different sources

    Homologous series: a group of organic compounds that have the same general formula, similar chemical properties, same functional group, and physical properties that gradually change from one member to the next.
    Hydrocarbons: compounds that contain hydrogen and carbon atoms only.
    Saturated: hydrocarbons that have single carbon to carbon bonds.
    Unsaturated: hydrocarbons that have one carbon to carbon double bond.
    Isomerism: forming isomers.

    What is the definition of 'general formula'?
    Also i know that alcohol have the functional group -OH, and alkenes have the carbon to carbon double bond, but what is the functional group for alkanes?
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    Homologous series: a group of organic compounds that have the same general formula, similar chemical properties, same functional group, and physical properties that gradually change from one member to the next.
    Hydrocarbons: compounds that contain hydrogen and carbon atoms only.
    Saturated: hydrocarbons that have single bonds only.
    Unsaturated: hydrocarbons that have one carbon to carbon double bond only.
    Isomerism: Same molecular formula, but different structural formula

    General formula: a type of empirical formula that represents the composition of any member of an entire class of compounds.

    Functional group: Alkane - C-C single bond
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    (Original post by Ranadosa)
    Are my definitions right? i keep getting different definitions from different sources

    Homologous series: a group of organic compounds that have the same general formula, exhibit similar chemical properties, have the same functional group, (and physical properties that gradually change from one member to the next.- I wouldn't say this because it's not true for larger carbon alkanes like sextane and decane but maybe it's okay for your spec) and all differ by a CH2 unit.

    Hydrocarbons: compounds that contain hydrogen and carbon atoms only.

    Saturated: hydrocarbons that have single carbon to carbon bonds( I would take out the carbon to carbon single bond thing because carboxylic acids and alcohols can also be saturated)

    Unsaturated: hydrocarbons that have one carbon to carbon double bond.

    Isomerism: forming isomers( certain compounds exist in different forms because of different arrangements of their atoms )

    What is the definition of 'general formula'? - a formula which is applicable to any compound in a homologous series.

    Also i know that alcohol have the functional group -O-H, and alkenes have the carbon to carbon double bond, but what is the functional group for alkanes? Alkanes don't have a functional group - this is why they are so non reactive.



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    Your homologos ones not right it should be Homologous series: a group of organic compounds that have the same general formula, similar chemical properties, same functional group, and physical properties vary predictably, consecutive members differ by CH2
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    The actual definition of a homologous series is - a series of compounds with the same functional group and that with each successive entry, they vary by a CH2. On OCR, the word successive is underlined, not sure for other exam boards. Everything else mentioned is a characteristic of a homologous series.
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    (Original post by Zx12r1)
    Your homologos ones not right it should be Homologous series: a group of organic compounds that have the same general formula, similar chemical properties, same functional group, and physical properties vary predictably, consecutive members differ by CH2
    alright thanks!!
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    (Original post by RasputinReborn)
    The actual definition of a homologous series is - a series of compounds with the same functional group and that with each successive entry, they vary by a CH2. On OCR, the word successive is underlined, not sure for other exam boards. Everything else mentioned is a characteristic of a homologous series.
    thanks! i'll check with the past papers
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    (Original post by Vigster)
    Homologous series: a group of organic compounds that have the same general formula, similar chemical properties, same functional group, and physical properties that gradually change from one member to the next.
    Hydrocarbons: compounds that contain hydrogen and carbon atoms only.
    Saturated: hydrocarbons that have single bonds only.
    Unsaturated: hydrocarbons that have one carbon to carbon double bond only.
    Isomerism: Same molecular formula, but different structural formula

    General formula: a type of empirical formula that represents the composition of any member of an entire class of compounds.

    Functional group: Alkane - C-C single bond
    thanks! helped a lot
 
 
 
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