IF ammonium chloride is formed by counter-current ... Wagner 1 has developed a mathematical model which accounts for the formation of the “Liesegang rings” and which predicts accurately ...

Ammonia is added to solutions of cobalt, nickel, and copper 2+ cations. First formation of the hydroxide precipitate is seen, then of the ammonia complex. Pour 0.1M solutions of Cu2+, Co2+, and Ni2+ ...