A solution of cupric hydroxide in aqueous ammonium
hydroxide (Cu(NH 3 ) 4 .
(OH) 2 ), which is capable of
dissolving cellulose if the concentration of
copper and ammonia are within given limits. The VISCOSITY (2) of a
cellulosic solution in cuprammonium hydroxide is
often used in quality control in the manufacture
of paper. (17 )