posted by Anonymous .
What is antacid? Why is sodium hydrogen carbonate an effective antacid but sodium hydroxide is not?
An antacid is the opposite of an acid. Antacids are over the counter medicines (usually) that you take for an acid stomach. Sodium hydroxide is an antacid, too, but it's too much of a good thing since it is very toxic to the system and WAAAAY to strong to swallow. Sodium hydrogen carbonate (sodium bicarbonate or bicarb) on the other hand is baking soda. It is a mild antacid and may be taken internally.
But there are also many weak base that can be taken internally, why is sodium hydrogen carbonate choosen to be antacid?