I have a Asus C300 and I was wondering if it is possible to uninstall chrome OS and replace it with Ubuntu. If it is possible can I also have some instructions on how to do it.
Well I believe the obvious answer to be Yes, if you have a Bootable USB with Ubuntu on it or an CD. But as mentioned below in the comments It may be harder since it was a chrome book.
For more Info check this question out: How do I install Ubuntu?
Also, possible duplicate: How to install Ubuntu 32-bit on Asus C300 chromebook
John Lewis made a good ROM for this Chromebook. I am currently running Ubuntu Gnome on my C300, but I've used KDE Neon, Kali Linux, and Debian. There are a few issues with the install. I had a huge issue with the touchpad not working, but it has been fixed in the 4.2.0-45 Kernel.
Give it a try. Be careful and definitely use the Chromebook Recovery Utility.
Oh, and I'm told sound works in most ASUS C300s, but is definitely doesn't work in mine. I think I may have done something wrong, but I really don't want to start over and redo everything.