Acetylacetone (see Exercise 43, part a), abbreviated acacH, is a bidentate
ligand. It loses a proton and coordinates as acac-, as shown below:
Acetylacetone reacts with an ethanol solution containing a salt of europium to
give a compound that is \(40.1 \% \mathrm{C}\) and \(4.71 \% \mathrm{H}\) by mass.
Combustion of \(0.286 \mathrm{~g}\) of the compound gives \(0.112\) \(\mathrm{g}
\mathrm{Eu}_{2} \mathrm{O}_{3}\). Assuming the compound contains only
\(\mathrm{C}, \mathrm{H}, \mathrm{O}\), and Eu, determine the formula of the
compound formed from the reaction of acetylacetone and the europium salt.
(Assume that the compound contains one europium ion.)