This is a battle between a sulfuric-acid based drain cleanser and a wet sponge. SPOILER: The sponge loses (although technically the acid is actually reacting with the water). I know you might be a fan of rooting for the underdog, but in this case the underdog gets its ass burnt off and handed to it. Reminds me of when I used to lock myself in my lab (read: bathroom) and mix random cleaners together in a bucket trying to invent a new, more powerful one. One time the smell alone made me pass out! That's when I knew I had something. "Had what -- the poison control hotline's 'Dumbf*** of the Month' award in the bag?" They sent me a magnet for the fridge and everything!
Hit the jump for the carnage.
Thanks to Tomtom, who once mixed baking soda and vinegar and made a little erupting volcano. Now do it with ammonia and bleach!