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    Diamond is a form of carbon.


    Diamond is

    a) a covalent compound
    b) an element
    c) an ionic compound
    d) a mixture

    ---
    I am aware it is made up purely of carbon but it is not on the periodic table, so is it classed as an element or not? What is the answer please
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    (Original post by PrinceUpsb)
    Diamond is a form of carbon.


    Diamond is

    a) a covalent compound
    b) an element
    c) an ionic compound
    d) a mixture

    ---
    I am aware it is made up purely of carbon but it is not on the periodic table, so is it classed as an element or not? What is the answer please
    It is a specific physical form of an element. This is known as an allotrope. Most elements have two or more distinct physical forms. For example, oxygen exists as oxygen gas and ozone.

    The different allotropes may arise due to different molecular arrangements, or due to different lattices of molecules and/or atoms.

    Carbon has several identified allotropes, diamond, graphite, fullerenes, graphene.
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    (Original post by charco)
    It is a specific physical form of an element. This is known as an allotrope. Most elements have two or more distinct physical forms. For example, oxygen exists as oxygen gas and ozone.

    The different allotropes may arise due to different molecular arrangements, or due to different lattices of molecules and/or atoms.

    Carbon has several identified allotropes, diamond, graphite, fullerenes, graphene.
    But they are all still classed as the element 'carbon', as well as having their specific 'allotrope' names? Am I right?
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    (Original post by PrinceUpsb)
    Diamond is a form of carbon.


    Diamond is

    a) a covalent compound
    b) an element
    c) an ionic compound
    d) a mixture

    ---
    I am aware it is made up purely of carbon but it is not on the periodic table, so is it classed as an element or not? What is the answer please
    The answer is A as it is a giant covalent lattice where each carbon is bonded to four others.
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    (Original post by Snowdog94)
    The answer is A as it is a giant covalent lattice where each carbon is bonded to four others.
    That is what I thought but the mark scheme says its B
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    (Original post by PrinceUpsb)
    But they are all still classed as the element 'carbon', as well as having their specific 'allotrope' names? Am I right?
    Well obviously as it consists of only Carbon atoms. Carbon has many allotrope like Graphite, Diamond, Buckminsterfullerene. I assume the answer is A because it's not a compound. Compounds have more than one element. I guess you could call it Carbon because that's what it is. It's like calling O2 or N2 Oxygen or Nitrogen, despite them being in the diatomic state.
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    (Original post by PrinceUpsb)
    Diamond is a form of carbon.


    Diamond is

    a) a covalent compound
    b) an element
    c) an ionic compound
    d) a mixture

    ---
    I am aware it is made up purely of carbon but it is not on the periodic table, so is it classed as an element or not? What is the answer please
    It is a form of carbon, and contains just that, so is classed as an element (allotrope). There are others, such as Graphite

    just think of oxygen, the molcule is diatomic (has two atoms) but we always consider the diatomic molecule to be the element oxygen. The same with the halogens

    A compound is always more than one type of atom. O2 is not a compound just as diomond isn't
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    (Original post by Snowdog94)
    The answer is A as it is a giant covalent lattice where each carbon is bonded to four others.
    No, it's not a compound, it's an element
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    Our teacher and revision guide says covalent compound of a lattice structure. But I do edexcel in my science exams so it may be less advanced?


    This was posted from The Student Room's iPhone/iPad App
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    (Original post by theGeezus)
    Our teacher and revision guide says covalent compound of a lattice structure. But I do edexcel in my science exams so it may be less advanced?


    This was posted from The Student Room's iPhone/iPad App
    Your teacher and revision guide are wrong (if they say that)!!!!

    Compounds MUST have two or more elements chemically combined...

    ... it's the definition of a compound.

    The very word "compound" means being made up of different parts.
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    It's an element since diamond is an allotrope which means it's an alternative form of the same element (carbon) in the same state (solid). Answer should be B, I think.


    This was posted from The Student Room's iPhone/iPad App
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    Should be B as it's an allotrope.

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