It depends a bit on the model, but in general yes you can. I haven't done it on a Chromebook, but I've completely wiped out ChromeOS and ran Arch on an Asus Ch

It depends a bit on the model, but in general yes you can. I haven't done it on a Chromebook, but I've completely wiped out ChromeOS and ran Arch on an Asus Chromebox (using instructions meant for the very similar C300 Chromebook). Worked perfectly, great little machine. Only hiccup was I had to flash a custom bios.