Hello, I am currently taking a college level chemistry class. I am struggling with this problem, any help would be greatly appreciated.(adsbygoogle = window.adsbygoogle || []).push({});

1. The problem statement, all variables and given/known data

We have a certain quantity of

[tex] CuSO_{4} \cdot \gamma H_{2}O [/tex]

If our sample is formed of (25,5% Cu), (12% S), (57,7% O) and (4.04% H), what is the value of gamma ?

2. Relevant equations

None given.

3. The attempt at a solution

I have determined the mass of 1mol of each element, the mass of 1mol of CuSO_4 (111.611g) and really, I'm stuck there.

Please don't spoil the fun for me, just give me some hints.

(edit) : I have done this much more :

Mass of 1mol Cu = 63.546g

(63.546g/111.611g)*100 = 56.94% Cu in CuSO_4

56.94%/25.5% = 2.2328 (increment factor)

So the mass of the hydrated CuSO_4 should be

111.611g * 2,2328= 249.21g

249.21g - 111.611g = 137.6g H2O

and 137.6g/18(g/mol)= 7.6 mol H2O

but it does not give me an integer...

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# Homework Help: Finding a stoichiometric coefficient

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