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# Quick guidance

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1. 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?

Cheers
2. (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?

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. Thanks a lot! I got my head around it a little while ago!

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