✔ 最佳答案
potassium tris(ethanedioato)ferrate(III) :
1. none
2. none
3. none
4. none
iron(III) nitrate(V) solution
1. brown precipitate is formed.
[Fe(OH2)6](3+) + 3OH(-) ------> Fe(OH)3
2. none
3. solution turns from yellow to red.
[Fe(OH2)6](3+) + SCN(-) ------> [Fe(NCS)(OH2)5](2+) + H2O
4. none.
(barium chloride solution would form white precipitate with sodium ethanedioate solution:
Ba(2+) + C2O4(2-) ------> BaC2O4
after forming complexes, the central ion and ligands are not free ions; they're tightly-bounded as a new chemical species. thus the complex is not reacting to reagents iron(III) would normally do.
2010-12-16 21:23:46 補充：
potassium tris(ethanedioato)ferrate(III) is green in color.
no reactions. neither chloride ion, hydroxide ion nor thiocyanate ion is stronger ligand than ethanediaote towards iron(III). they cannot substitute the ethanedioate and react with iron(III).
2010-12-16 21:26:21 補充：
as mentioned, the complex is different from the separated ions. they're tightly bounded, unless an even stronger ligand comes and substitute the original ligands.
no free iron(III), so HO(-), Cl(-) & NCS(-) won't react with iron(III);
no free ethanedioate, so no precipitate with barium ion.
2010-12-20 11:21:56 補充：
唔係.
[Fe(OH2)6](3+) 係講緊溶落水之後, 粒iron(III) 係咩狀態.
iron(III) nitrate(V) 仍然係Fe(NO3)3 .
