Question

What are the chemical reactions going on if I add these to the following equation:

Fe³⁺     +      SCN^1-    ↔     FeSCN²⁺

^a) Fe(NO₃)₃

_b)NH₄NCS

c)AgNO₃

_d)NH₃

_e)SnCl₂

_f) Na₂HPO₄

_g)Heat

_{h) Ice}

Answer 1

Fe³⁺ (yellow) + SCN^- (colorless) <--> [FeSCN]²⁺ (dark red)

Following additions effect the equillubrium

A) Fe(NO₃)₃ ----> Fe³⁺ + 3NO₃^-

when you add your Fe(NO3)3 solution and it dissociates in solution, you are effectively adding in Fe3+ ions.The reaction will shift to the right. Therefore, you will be making more [FeSCN]2+ and the reaction will become a darker red.

B) NH₄NCS ----> NH_4⁺ +NCS-

when you add your NH₄NCS solution and it dissociates in solution, you are effectively adding in NCS- ions. The reaction will shift to the right. Therefore, you will be making more [FeSCN]2+ and the reaction will become a darker red