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    calculate the mass in grams of a single atom of sodium

    Ok so i did moles=6.02x10^23 / 23= 2.617391304x10^22 is this right?
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    moles = mass/mr rearrange
    the equation would be moles * mr so it should be 6.02x10^23 * 23
    hopefully i'm right :/
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    Think about your answer. Does it sound reasonable to you?
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    (Original post by Azurefeline)
    Think about your answer. Does it sound reasonable to you?
    no, but i don't know how to do it
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    it is:

    Avogardos number/23 to find moles and then moles * Mr to get mass.

    Give that ago and then let me know what you get please!
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    (Original post by kandykissesxox)
    no, but i don't know how to do it
    Ok, so you answered "am I right".

    Now, molar mass is the weight of one mole of that type of atom. And you need to find out the weight of a single one of those atoms. Remember that 1 mole is just a number (albeit very large). What are you thinking now? Do you have an idea, or the answer?
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    (Original post by Azurefeline)
    Ok, so you answered "am I right".

    Now, molar mass is the weight of one mole of that type of atom. And you need to find out the weight of a single one of those atoms. Remember that 1 mole is just a number (albeit very large). What are you thinking now? Do you have an idea, or the answer?

    ok so would you do 6.02x10^23 is 23g therefore 23/6.02x10^23 = 3.8205x10^23
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    (Original post by kandykissesxox)
    ok so would you do 6.02x10^23 is 23g therefore 23/6.02x10^23 = 3.8205x10^23
    That's exactly what I would do, but double check the answer to your calulation (sense check - is that plausible?) I think you probably mis-typed though
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    (Original post by Azurefeline)
    That's exactly what I would do, but double check the answer to your calulation (sense check - is that plausible?) I think you probably mis-typed though
    ok i have checked, thank you! could you please help me on one last question?


    calculate the number of oxygen molecules that react with 2.6g of sodium.

    I have done so far: moles= 2.61/23
    moles=0.1134782609

    then plugged it into the avagadro equation so the moles x 6.02x10^23
    am i taking the right steps?
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    Atomic mass/6.02x10-23

    23/6.02x10-23 = 3.819x10-23 grams
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    (Original post by TajwarC)
    Atomic mass/6.02x10-23

    23/6.02x10-23 = 3.819x10-23 grams

    a bit late haha
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    (Original post by kandykissesxox)
    ok i have checked, thank you! could you please help me on one last question?


    calculate the number of oxygen molecules that react with 2.6g of sodium.

    I have done so far: moles= 2.61/23
    moles=0.1134782609

    then plugged it into the avagadro equation so the moles x 6.02x10^23
    am i taking the right steps?
    Important things to consider: an oxygen molecule is not an oxygen atom. Writing out the equation for the reaction of sodium and oxygen will help with balancing as well
 
 
 
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