SN very durable even in a water solution .
Solid – not very reactive (slowly oxidize over long time). Clamps fine. Air-tight container can be opened and closed, won't go bad.
Solution (strong) – labs store it at room temp, open & close, a bit of oxygen is fine. Homemade solutions are not purified water, so should not be stored, but potency is maintained for at least several hours..
More data sheets & temperature -