For one page of a novel, which with my usual formatting is around 500-600 words, it takes me about an hour on a good day. On a bad day, it takes me two or three. (I'm a slow writer, most of that time is just me thinking, haha) For one page of a comic, anywhere between four and nine hours depending on the content of the panels
If we're talking novel chapters, probably closer to seven or eight hours total. I take it pretty slow on chapters to reduce my editing load later on.