Cupric periodates

A number of periodates has been obtained by dissolving cupric hydroxide or carbonate in a solution of periodic acid, and also by the interaction of sodium periodate, NaIO₄, and solutions of cupric salts. They have the formulae 2CuO,I₂O₇,6H₂O; 4CuO,I₂O₇,H₂O; 4CuO,I₂O₇,7H₂O; and 5CuO,I₂O₇,5H₂O.