transition metals (aqa)Watch
for aluminium aqua complex with excess OH-
Al(H2O)3(0H)3 + 3 OH- ---> [Al(OH)6]^3- + 3 H20
That pesky OH-...
But my book show's it forms Al (OH)^-4
When aluminium react with excess ammonia
However, reacting with excess ammonia will substitute water ligands for ammonia ligands. Ammonia only acts as a source of OH- ions when it's added dropwise, not in excess.
I can't think of any way how you'd form [Al(OH)4]- from your starting position by reacting with excess ammonia, or anything for that matter.