How long can melted chocolate last?
Freezing chocolate is not ideal, because when it defrosts it can 'bloom' - you may have seen this happen with chocolate that has been stored unwrapped in the fridge. It gets an unsightly white coating.

If you absolutely must freeze it, wrap it very well, and bring the temperature down slowly. First let it cool out of the fridge, then in the fridge for several hours, then in the freezer.