Why does berocca and coke explode?

Answer 1

The answer is probably similar to why Mentos and Coke explode. It was written about in New Scientist and explored in Mythbusters in about 2008. In that case, the mint mentos has small pits in the rough surface, which increases the amount of surface area of the mint. Carbon Dioxide in Coke (CO2) forms in the small pits very quicky. The same experiement will not work with Fruit mentos, which has a shiny hard surface. There is evidence that the arabic gum on the surface of sweets also works to make the reaction faster, but no-one has explained why. It works better with Diet Coke, probably because the artifical sweetener is more reactive that regular sugar, creating more gas. As gas forms it expands the volume inside the bottle and creates pressure. Needing a release, it explodes out of the mouth of the bottle. While there may not have been a particular study of berrocca, those big tablets also have a large, pitted surface area. In addition, Berocca contains socium bicarbonate, which reacts with acids to create CO2, so you get even more carbon dioxide forming. Without wasting money, you can create a similar chemical reaction by using common vinegar and Soda Bicard, both much cheaper that coke or sweets and available from most supermarkets.