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quick complex ion question

is it acceptable to write both

[Al(H20)3(OH)3]

and

[Al(OH)3]

if they ask you to write an eq about the formation of [Al(OH)6]^-3

(this for AQA chem exam board)

Reply 1

Goodkat

Yes you can write it either way, although personally I like to include the waters and it makes ligand substitution reactions etc look more obvious as to what is going on.

Reply 2

bahbahbah

yeah if you understand it you might as well take 2 seconds to write out the full thing with the water so the examiner knows you understand.

Reply 3

silent ninja

Some mark schemes dont show the waters (is that even in a word?), others do. It depends on the wording of the question, like:
"write an equation to show the formation of the precipitate" without water on this is fine

but "write an equation showing ligand substitution/showing what happens in this reacion" now you have to show the waters because the question is about ligands and a change occurring

But its not clear cut so I would include the waters whether they ask for it or not.