# Chemistry

A 32.907-g sample of a hydrate of Au (CN)3 contains 5.406 g H2O

What is the formula for the hydrate?
What is the percent water in this compound?
What mass of this hydrate contains 100.0 g H2O?

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1. mass Au(CN)3 + H2O = 32.907g
mass H2O = 5.406g
mass Au(CN)3 = 32.907-5.406 = ?g

Convert ?g Au(CN)3 to mols = ?
Convert 5.406g H2O to mols ?

Find the ratio of mols H2O to 1 mol Au(CN)3 to find the formula.

%H2O = (mass H2O/total mass)*100 = ?

For part c, use the percent formula you just finished, substitute the numbers you want and solve for total mass.

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