need help with chemistry please

Question

If 0.2486 moles of aluminum sulfur react with fluorine, to make aluminum fluoride and elemental sulfur (S), how many moles of fluorine are used?

Answer 1

Aluminum generally forms Al⁺³ ions while Sulfur forms S^-2 ions

So Al₂S₃ would be the combination of aluminum and sulfur to make a neutral compound.

Fluorine is stable in the elemental form as F₂ so our general reaction is:

Al₂S₃ + F₂ ---> AlF₃ + S

To balance this we need to make some adjustments to the equation as follows:

Al₂S₃ + 3F₂ ---> 2AlF₃ + 3S

Now that we have the balanced chemical equation we see that :

every 1 mole of Al₂S₃ uses 3 moles of F₂

If I started with 5 moles of aluminum sulfide, using dimensional analysis, this becomes:

5 moles Al₂S₃ x 3 moles F₂ = 15 moles of F₂

1 mole Al₂S₃