Is it possible to open, say a turbo 24 or 48 yeast, use half of it for a half sized smaller run, stuff the rest of it in a ziplock baggie and refridgerate until a later time.

Reason is, just learning the ropes and being able to do multiple 'experiments' with smaller batches is speeding up my learning curve.

Just don't know if the exposed other half in the packet would go bad.