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  1. Karen72's Avatar
    • Full Member
    • Posts: 88
    Quick guidance
    Hey Guys am not sure if l'am thinking of something else when calculating ions in a compound but if l am can someone point me in the right direction please

    3.42g of Al2(SO4)3

    I did M/GFM got 0.01 mol
    then 0.01* 6.02*10^23= 6.02*10^21 ions

    Am l thinking of something else entirely? :confused:

    Cheers
  2. clownfish's Avatar
    • Benevolent Member
    • Posts: 667
    Re: Quick guidance
    (Original post by Karen72)
    Hey Guys am not sure if l'am thinking of something else when calculating ions in a compound but if l am can someone point me in the right direction please

    3.42g of Al2(SO4)3

    I did M/GFM got 0.01 mol
    then 0.01* 6.02*10^23= 6.02*10^21 ions

    Am l thinking of something else entirely? :confused:

    Cheers
    You've found the number of molecules.
    But the compound is made up of Aluminium and sulfate ions, so one molecule = 2+3=5 ions, so you need to multiply the number of molecules by 5 to get the number of ions.
  3. Karen72's Avatar
    • Full Member
    • Posts: 88
    Re: Quick guidance
    Thanks a lot! I got my head around it a little while ago!
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