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give me 5 differences between allotrophes and isotopes?

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  • 1 decade ago
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    Allotropy (Gr. allos, other, and tropos, manner) is the name applied by Jöns Jakob Berzelius to the property possessed by specific pure elemental substances that can exist with different crystalline structures; the various forms are known as allotropes.

    [edit] Definition

    Allotropy is the ability of a chemical to exhibit a number of different and physically distinct forms in its pure elemental state. Carbon, for instance, can exist as graphite, diamond , and fullerene (including the buckyball, C60). Typically, elements capable of variable coordination numbers and/or oxidation states tend to exhibit greater numbers of allotropic forms. Another contributing factor is the ability of an element to catenate. Allotropes are typically more noticeable in non-metals and metalloids. The term allotropes may also be used to refer to the molecular forms of an element (such as a diatomic gas), even if there is only one such additional form.

    Allotropes should not be confused with changes of state/phase or isomers.

    [edit] Differences in physical properties

    On a nanoscopic level, the structure of allotropic forms can be drastically different. As such, their macroscopic properties may be very different too. To use the same example of carbon allotropes, diamond forms a tetrahedral lattice structure. As such, it is highly crystalline, has a high transmittance and is very hard on a macroscopic level. Graphite on the other hand forms broad flat sheets of hexagonal carbon rings with a conjugated electronic structure. These sheets are only weakly bonded together and are more or less free to slide past each other. As a result, graphite is semiconductive, has a negligible transmittance and is very soft. Graphite is often used in lubricants. Finally, fullerenes (and their derivatives, nanotubes) are a molecular allotrope and have chemical properties altogether different to any other form of carbon.

    Allotropes tend to be affected by pressure and temperature, and many will only be stable given the correct conditions. For instance, iron only changes from ferrite to austenite above 723°C, and tin undergoes a process known as tin pest at 13.2°C and below.

    [edit] Examples

    Some other good examples of allotropes include:

    Phosphorus:

    Red Phosphorus - polymeric solid

    White Phosphorus - crystalline solid

    Black Phosphorus - semiconductor, analogous to graphite

    Oxygen:

    dioxygen, O2 - colourless gas

    ozone, O3 - pale blue gas/deep blue liquid

    tetraoxygen, O4 - red solid

    Sulfur:

    Plastic (amorphous) sulfur - polymeric solid

    Rhombic sulfur - large crystals composed of S8 molecules

    Monoclinic sulfur - fine needle-like crystals

    Molecular sulfur - sulphur tends to form ring molecules such as S7 and S12

    Carbon:

    Main article: Allotropes of carbon

    diamond

    graphite

    Isotopes are any of the several different forms of an element each having different atomic mass (mass number). Isotopes of an element have nuclei with the same number of protons (the same atomic number) but different numbers of neutrons. Therefore, isotopes have different mass numbers, which give the total number of nucleons—the number of protons plus neutrons.

    The term isotope was coined in 1913 by Margaret Todd, a Scottish doctor, during a conversation with Frederick Soddy, to whom she was distantly related by marriage. Soddy, a chemist at Glasgow University, explained that it appeared from his investigations as if several elements occupied each position in the periodic table. Hence Todd suggested the Greek for "at the same place" as a suitable name. Soddy adopted the term and went on to win the Nobel Prize for Chemistry in 1921 for his work on radioactive substances.

    A nuclide is any particular atomic nucleus with a specific atomic number Z and mass number A; it is equivalently an atomic nucleus with a specific number of protons and neutrons. Collectively, all the isotopes of all the elements form the set of nuclides. The distinction between the terms isotope and nuclide has somewhat blurred, and they are often used interchangeably. Isotope is best used when referring to several different nuclides of the same element; nuclide is more generic and is used when referencing only one nucleus or several nuclei of different elements. For example, it is more correct to say that an element such as fluorine consists of one stable nuclide rather than that it has one stable isotope.

    In scientific nomenclature, isotopes and nuclides are specified by the name of the particular element, implicitly giving the atomic number, followed by a hyphen and the mass number (e.g. helium-3, carbon-12, carbon-13, iodine-131 and uranium-238). In symbolic form, the number of nucleons is denoted as a superscripted prefix to the chemical symbol (e.g. 3He, 12C, 13C, 131I and 238U).

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  • Lisa
    Lv 4
    4 years ago

    Isomers have exactly the same compounds but different molecular arrangements. They are something like fraternal twins. Isotopes have the exact same electronical configuration. In other words they have the same no. of electrons and protons but differ only by the number of neutrons. You can call them idential twins. What you want here is the isotope. There are a few isotopes of carbon, namely 12-Carbon, 14-Carbon and even 60-Carbon used to make buckministerfullerene, or the buckyball. The pure form of carbon will only have isotopes, but assuming you are involving carbon in a reaction an isonomer may be produced.

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  • 1 decade ago

    allotrope is an element that can exsist in different forms bt the same state of matter e.g carbons allotrophes are graphite, diamonds

    isotope is an element that exsist in different forms which have the same atomic number bt a different neucleon mass e.g C-12 and C-14

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  • 1 decade ago

    allotropes are

    •fact: like atoms tend to bond together

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