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"State the n umber of moles of sulfur atoms in 0.3mol of Fe2(SO4)3" Watch

1. The answer is 0.9mol but how?
2. 3 sulphur atoms in each molecule, 0.3 moles of molecule

0.3*3=0.9
3. 0.3 mol of Fe2(SO4)3.
Number of moles of sulphur atoms is 0.9mol
Say we had 1 mol of Fe2(SO4)3 molecules
Therefore we would have 2 moles of Fe3+ ions and 3 moles SO4 2- ions in 1 mol of Fe2(SO4)3.

1 mole is 6.022x10^23 ions/molecules/atoms

In 3 moles of SO4 2- ions there is 3 moles of Sulphur atoms. So in 1 mole of iron sulphate there is 3 moles of sulphur atoms.

If we start off with 0.3 mol of iron sulphate therefore we would have 3*0.3 moles of sulphur atoms. Which is 0.9 moles.

Hope this alright moles are quite confusing.

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Updated: April 25, 2016
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