I learned 4 new things yesterday:
Phosphoric acid (H3PO4) removes iron oxide (Fe2O3).
Common soda contains phosphoric acid.
Contrary to popular belief, or whatever belief there is, the phosphoric acid in soda is far too dilute to react with the ammonia in Windex. Or, they don't react at all.
It takes a while to boil soda down to get a more concentrated phosphoric acid.
You know... chemistry is actually interesting when it becomes practical.
