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It would only carbonate to the extent of any residual sugar that had not been fermented out due to not checking final gravity, and probably be extremely under-carbonated. This is where a hydrometer is indispensable.
It is possible to bottle before fermentation is complete and have enough sugar left so that it carbonates in the bottle, but that's pretty risky. You've got to get everything EXACTLY RIGHT, or you've got either flat beer or glass grenades.
Something I've read about but never tried is reserving a measured amount of boiled wort before pitching the yeast, and keeping it in the fridge until fermentation is complete. Then you add it at bottle time. The unfermented wort contains the sugar to carbonate in the bottle.
Brad's got article about it here: http://beersmith.com/blog/2010/03/22/krausening-home-brewed-beer/
Or you could get a keg system. Do that and you may never bottle a batch again. I haven't.