What is the name of a piece of lab glass tube shaped but at one end is porous that allows dispersed bubbles into finer bubbles

The piece of lab equipment you're referring to is likely a **sparger** or a **bubbler**. A sparger typically consists of a tube with a porous end that allows gases to be introduced into a liquid in the form of fine bubbles. This is commonly used in various applications including chemical reactions, fermentation, and aeration processes. There are different types of spargers, such as sintered glass spargers, which have a porous material that helps in dispersing the gas efficiently.