Is it possible to switch over a stick of ram from one laptop to another?

Say, I were planning to upgrade my new laptops RAM. Yet, I had a broken Lenovo y580 (LCD messed up on me) can I salvage the 8gbs ram and switch it over to have 12Gbs of ram, instead of the 4 my newer laptop has to offer? Or would this be dangerous, and unhealthy for my newer laptop. (Sager NP8651)

Is it possible to switch over a stick of ram from one laptop to another?