If a divalent metal ion is inserted in the center of the porphine ring, its charge will exactly balance the two negative charges of the dianion. Write a balanced equation for the reaction of tetraphenylporphyrin (which you can abbreviate as TPP) with cupric acetate [Cu(CH3COO)2] to give acetic acid [CH3COOH] and a copper(II) ion in the center of the TPP dianion.