Нитрат меди (II)

[Erica Sklodowska 6]

Cu + 4HNO₃ → Cu(NO₃)₂ + 2NO₂ + 2H₂O

В ходе данной реакции получился темно-зеленый раствор. Присутствием каких ионов может быть обусловлена такая окраска раствора?

Ведь теоретически раствор нитрата меди имеет синюю окраску...

 

[Paul_K 470]

When the copper is first oxidized, the solution is very concentrated, and the Cu²⁺ product is initially coordinated to nitrate ions from the nitric acid, giving the solution first a green, and then a greenish-brownish color.  When the solution is diluted with water, water molecules displace the nitrate ions in the coordinate sites around the copper ions, causing the solution to change to a blue color.

https://www.angelo.edu/faculty/kboudrea/demos/copper_HNO3/Cu_HNO3.htm