system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Why is it that some of the worlds most caustic chemicals and liquids do not interact with the glass beakers they're contained in while they dissolve pennies like cotton candy in water.
gpt
Glass is not very reactive and thats why it is used to contain those chemicals. There are some chemicals that react with glass and they obviously can't be held in glass containers. 

On the other hand metals are strong and heavy but most of them all very reactive for example they oxidate easily (rust). So it actually doesn't take a lot from chemical to dissolve some metals.

Why some materials are reactive with others comes mainly from their electron structure.