The coke and mentos experiment is investigation of the chemical change and understanding the way substances and gases work, the experiment shows the way mentos( a hard candy) reacts with coke(soft drink), and creates a mild explosion .
It is basically the process of bubbles that are called nucleation, it is when substances form on their own to make a reaction, carbon dioxide make up the bubbles, nucleation is not very explosive when tested with mentos, the reaction is made because mentos have little openings on the surface that enables the carbon dioxide to seep in to creat a minor explosion.
The experiment is used in the real world as it imitates what a situation of carbon dioxide, nucleation and how it would react to substances.