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How many moles..... Watch

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    How many moles of electrons are there in one mole of OH- Ions? I know the answer but not sure how to go about tackling this question.
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    how many electrons are there in an OH- ion? 10 (I think...)

    ratio= 1 OH- : 10 e-

    so in 1 mole of OH-, there's 10 moles of e-
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    (Original post by LegendX)
    How many moles of electrons are there in one mole of OH- Ions? I know the answer but not sure how to go about tackling this question.
    O has 8 electrons so 8 moles
    H has 1 electron so 1 mole
    the negative sign is +1 electron so another mole which equals 10.
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    (Original post by word2yamother)
    You can only get moles of atoms not moles of subatomic particles
    Not true :nah:

    Moles is just the SI unit for amount, so it can be for atoms, ions, molecules, electrons etc.
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    (Original post by word2yamother)
    You can only get moles of atoms not moles of subatomic particles
    You can get moles of H+ ions, which are protons
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    That's not true.
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    So basically when it says a question like this, you break it down so for example if it said, how many m,es of electrons in SO4 2- charge, it would be

    16 electrons frm sulfur
    32 electrons from oxygen
    And 2 more cus its 2- ?

    But I don't understand why the charge on the ion makes you add electrons.
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    (Original post by LegendX)
    So basically when it says a question like this, you break it down so for example if it said, how many m,es of electrons in SO4 2- charge, it would be

    16 electrons frm sulfur
    32 electrons from oxygen
    And 2 more cus its 2- ?

    But I don't understand why the charge on the ion makes you add electrons.
    The -ve charge is due to excess electrons (similarly +ve charge is from a lack of electrons.)

    The number of protons doesn't change (otherwise the element would change) but electrons can be lost/gained to give charged ions...
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    (Original post by Hearty_Beast)
    The -ve charge is due to excess electrons (similarly +ve charge is from a lack of electrons.)

    The number of protons doesn't change (otherwise the element would change) but electrons can be lost/gained to give charged ions...

    so the moles of electrons in say ' 2 SO4 2- ' would be:

    164?
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    (Original post by LegendX)
    so the moles of electrons in say ' 2 SO4 2- ' would be:

    164?
    S = 16e
    Each O = 8e
    2- = 2e
    SO42- = 16 + (8*4) +2 = 50e

    So 2SO42- = 2x50=100e

    I think you might have used the mass number of sulfur instead of the atomic number.
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    (Original post by Hearty_Beast)
    The -ve charge is due to excess electrons (similarly +ve charge is from a lack of electrons.)

    The number of protons doesn't change (otherwise the element would change) but electrons can be lost/gained to give charged ions...
    in SO42- where did the excess of 2 electrons come from? if the S supplies 16 electrons and the O supplies 32 electrons surely it would be 48 electrons in total and not 50?
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    (Original post by LegendX)
    in SO42- where did the excess of 2 electrons come from? if the S supplies 16 electrons and the O supplies 32 electrons surely it would be 48 electrons in total and not 50?
    neutral S provides 16 electrons, neutral O provides 32 electrons

    you have a 2- charge on the ion so you have to add 2 more electrons
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    As previously stated, a mole is simply an amount. You could have a mole of moles if you really wanted to. Or a mole of voles if that's more your thing :rolleyes:
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    (Original post by illusionz)
    As previously stated, a mole is simply an amount. You could have a mole of moles if you really wanted to. Or a mole of voles if that's more your thing :rolleyes:
    How many mole of particles are there then in one mole of electrons?
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    (Original post by anillatoo)
    How many mole of particles are there then in one mole of electrons?
    Seeing as electrons are elementary particles (leptons), 1.
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    (Original post by illusionz)
    Seeing as electrons are elementary particles (leptons), 1.
    Alright, so if I understood your reasoning, one mole of proton contains 3 moles of quarks which each contains one mole of 6.02*10^23 particles?
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    (Original post by anillatoo)
    Alright, so if I understood your reasoning, one mole of proton contains 3 moles of quarks which each contains one mole of 6.02*10^23 particles?
    Well I wouldn't normally think about it in that way - I only brought up elementary particles because your question seemed rather odd. I guess you could argue that each proton contains 3 quarks so therefore a mole of protons contains 3 moles of particles, but it's not something anyone would ever ask.
 
 
 
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