Question

How many moles of aluminum sulfide in 155 gram of aluminum?

Answer 1

`0`

Explanation:

If you just have a pure sample of `155 \ "g"` of aluminium, then there can be no sulfide ions in there, and so there will be `0` moles of aluminium sulfide.

Perhaps you meant the opposite, How many moles of aluminium in `155 \ "g"` of aluminium sulfide?

If so, the amount can be calculated as follows.

Aluminium sulfide has a chemical formula of `Al_2S_3`, and has a molar mass of `150.158 \ "g/mol"`.

So here, there exist

`(155color(red)cancelcolor(black)"g")/(150.158color(red)cancelcolor(black)"g""/mol")~~1.03 \ "mol"`

Since there are `1.03` moles of aluminium sulfide, then that must mean that there are `1.03*2=2.06 \ "mol"` of aluminium ions in the sample, due to the chemical formula.