tongue bite is chemical burn from alkaline smoke.
tongue burn is a heat burn. it can happen but it's extremely rare.
>>2102858the heat content of a gas is quite low compared to a liquid at the same temperature, because there's so little thermal mass. It's easy to scald your tongue with a sip of hot coffee, because that one sip has more actual *heat* in it than the smoke from the entire bowl of tobacco. to make things worse, your tongue has a lot of blood flowing through it, and that blood is quickly carrying heat away from your tongue, making it hard to build up enough heat through repetitive exposure. It's probably possible to burn your tongue with heat, but it would take an extremely short stem - an inch or so - so that your tongue gets hit with smoke at essentially combustion temperature, that's probably enough to give you a heat burn if you puff it fast enough. You can tell a heat burn because it happens right away, you puff and your tongue immediately burns. If the burn builds up over the course of the pipe, or appears shortly afterwards, then it's a chemical burn.
the only pipe that has given me an actual heat burn was a Rattray Polly (pic related), the stem is just over an inch long but there is no shank. I've also gotten a heat burn from a meerschaum cigar holder (stem < 1" long) if I smoke the cigar down to the nub. But that's it, every other time I've gotten burned in my two decades of pipe smoking has been tongue bite - a chemical burn.
