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    Does anyone know how to calculate the expected mass of one mole of alpha particles (4He2+ ions)? The questions tells you that the mass of one proton is 1.6725 x 10^-24 and the mass of one neutron is 1.6748 x 10^-24 and the Avogadro constant is 6.0225 x 10^23.
    Any help would be appreciated as I'm really stuck.
    Thanks
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    (Original post by issyafd1)
    Does anyone know how to calculate the expected mass of one mole of alpha particles (4He2+ ions)? The questions tells you that the mass of one proton is 1.6725 x 10^-24 and the mass of one neutron is 1.6748 x 10^-24 and the Avogadro constant is 6.0225 x 10^23.
    Any help would be appreciated as I'm really stuck.
    Thanks
    How many protons and how many neutrons make up one alpha particle?

    Knowing that work out the mass of one alpha particle.

    Now work out the mass of 1 mole of alpha particles.
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    (Original post by TeachChemistry)
    How many protons and how many neutrons make up one alpha particle?

    Knowing that work out the mass of one alpha particle.

    Now work out the mass of 1 mole of alpha particles.
    Thank you so much
    I got 8.0636457 is that right?
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    (Original post by issyafd1)
    Thank you so much
    I got 8.0636457 is that right?
    No but I can see why it's wrong. Tell me how many protons and how many neutrons you have. Also don't forget the unit for your answer.
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    1.0039 x 10^-23 ?
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    (Original post by issyafd1)
    1.0039 x 10^-23 ?
    No - you were closer the first time!

    An alpha particle is a helium atom without its two electrons (which have a negligible mass). What's the mass of a mole of helium atoms?
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    (Original post by TeachChemistry)
    No - you were closer the first time!

    An alpha particle is a helium atom without its two electrons (which have a negligible mass). What's the mass of a mole of helium atoms?
    Ah thank you that makes a lot more sense

    (1.6725X10^-24 X 2) + (2X 1.6748X10^-24 X 2) = 6.6946 x 10^-24
    6.6946 x 10^24 x 6.0225 x 10^23 = 4.03182285

    Is it right now?
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    (Original post by issyafd1)
    Ah thank you that makes a lot more sense

    (1.6725X10^-24 X 2) + (2X 1.6748X10^-24 X 2) = 6.6946 x 10^-24
    6.6946 x 10^24 x 6.0225 x 10^23 = 4.03182285

    Is it right now?
    Yes. Unit?
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    Thank you so much I think the units are grams.

 
 
 
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