Fe3+ + SCN–  FeSCN2+ KSCN = colourless, Fe(NO3)3 = colourless mixed = brown, red, rusty, etc. , FeSCN2+ provides the colour 10. 2- Darker brown , (more SCN–) shift right (toward FeSCN2+) 3- Darker brown , (more Fe3+) 4- Lighter brown , (less Fe3+) shift left (away from FeSCN2+) 11. None (they are all the same) , Only temperature changes Kc 12/10/99

Equilibrium Lab 12 Fe3+ SCN– FeSCN2+  SCN– =    None* 12/10/99 12 Fe3+ SCN– FeSCN2+  SCN– =    None*  Fe3+ =    Na2HPO4**  Fe3+ =    Fe(NO3)3*** *(With  SCN–, only a  SCN– will reestablish equilibrium. None of these chemicals work. (addition of Na2HPO4 can decrease FeSCN2+ to its original [ ], but not the others). **Fe3+ has been increased. The only way to reestablish equilibrium is to decrease Fe3+. ***Fe3+ has decreased. The only way to reestablish equilibrium is to increase Fe3+.

For more lessons, visit www.chalkbored.com The Haber process 12/10/99 A second application of Le chatelier’s principle (film = 10 min) For more lessons, visit www.chalkbored.com