[ichigoonwall]

I haven't been able to figure this problem out.  I tried setting up all sorts of ratios, even including moles.  Anyone want to give it a go?

In a chemical atomic weight determination, the tin content of 3.7692 g of SnCl4 was found to be 1.7170 g.  If the atomic weight of Chlorine is taken as 35.253, what is the determined value for the atomic weight of tin from this experiment?

I already know the answer, 118.64.  It was given.  What I'm stuck on is the process.  Can somebody explain how to set this up?  Thanks.

[Dan]

1. If you have 3.7692 g SnCl₄, and 1.7170 g is Sn, how many grams of Cl must you have? (assuming it's pure)

2. You know how many grams of Cl you have, how many moles is that?

3. You know how many moles of Cl you have, so how many moles of Sn do you have? (remember, it's SnCl₄)

4. You know how many moles of Sn you have, and the mass of the Sn, so now you can work out the atomic weight of Sn... (remember, the units of atomic weight are g/mol...)

Edit: I disagree with an answer of 118.64. If you do not do any rounding at all in these calculations you get 117.98. However, the atomic weight of Cl you have given, 35.253, is incorrect. I assume this is a typo, it should be 35.453, in which case I get 118.65.