When you are doing the penny experiment to turn the outside gold/silver.......can you leave the penny in the soilution (zinc powder + Sodium Hydroxide)....or willl the zinc powder combust after awhile in the water.
Anyway, the container says keep away from water....so I'm confused....will it like ignite later on if I leave the penny in solution over the weekend........it was just a spoonful of zinc powder....
Also
How do you dispose of the solution and zinc powder that is at the bottom of the beaker?
Thanks