So, basically, if you want to chance it, go ahead. It could happen, and the publisher could check, or it might not.
Well, like Terry said, with something like an entire magazine article at a popular blog for instance, that could pose a problem. But a chapter from a book? Let's just say I'm going to have to see a list of books that have been turned down by reputable publishers before I start worrying. And, I don't mean POD publishers. My mama was from a small town in Tennessee that "you would never find" by the way. Especially since the tornado blew it away a couple of years ago. This is my final word incidentally. Life's too short.