A 1.00 L solution contains 4.00×10-4 M Cu(NO3)2 and 3.000×10-3 M ethylenediamine (en). The Kf for Cu(en)2^2+ is 1.00×10^20. What is the concentration of Cu2+(aq ) in the solution?

Alidded glass container is filled with a colored gas. after a period of time, it is observed that the gas is uniformly spread throughout the box and that the movement has slowed considerably. next, a warm iron plate is carefully placed under the box. why is there resumed movement of the gas in the container?