Chrome Won't Go Away
I'm guessing you have what's known in Unix as a zombie process. Unlike the less friendly dead people, zombies in your computer won't eat your brains, and they also won't do much of anything else. They don't take up any resources. It's basically just going to sit there until you reboot, or you lop its head off. OS X doesn't seem to tend its fences when it comes to zombies. I can think of a game or two they should play which would help them out with this a bit...

For more info on Zombies, see:
https://en.wikipedia.org/wiki/Plants_vs._Zombies

or, even more helpfully:
https://en.wikipedia.org/wiki/Zombie_process