RAM Upgrade for Mid-2010 MacBook
You should search for info about your mac on Everymac.com. I searched there for your mac and assuming I did it right I found this brief comment.


  Apple officially supports a maximum of 4 GB of RAM, but third-parties have determined that it actually supports 8 GB of RAM running Mac OS X 10.6 "Snow Leopard" and 16 GB of RAM running OS X 10.7.5 "Lion" or higher and the latest EFI update.


Sounds like it depends on which system you are running. I suggest you go there and see what else you can find or go to OtherWorldComputing or here  which reports they sell upgrade kits for your specific Mac.