Question

If a copper acetate hydrate, Cux(C2H3O2)y zH2O compound is found to contain 31.82% Copper, 59.14% acetate, and the remainder is water. What is the empirical formula of this compound

Answer 1

Answer is: empirical formula is Cu(C₂H₃O₂)₂ · H₂O.
If we use 100 grams of compound:
m(Cu) = 0,3182 · 100 g = 31,82 g.
n(Cu) = m(Cu) ÷ M(Cu).
n(Cu) = 31,82 g ÷ 63,55 g/mol.
n = 0,5 mol.
m(C₂H₃O₂) = 0,5914 · 100 g = 59,14 g.
n(C₂H₃O₂) = 59,14 g ÷ 59,14 g/mol.
n(C₂H₃O₂) = 1 mol.
m(H₂O) = 100 g - 59,14 g - 31,82 g = 9,04 g.
n(H₂O) = 9,04 g ÷ 18,02 g/mol.
n(H₂O) = 0,5 mol.
n(Cu) : n(C₂H₃O₂) : n(H₂O) = 0,5 mol : 1 mol : 0,5 mol.
n(Cu) : n(C₂H₃O₂) : n(H₂O) = 1 : 2 : 1.