Okay kiddo, let's imagine that you have two types of toys - red ones and blue ones. Now, let's divide your toy box into two parts - one for red toys and one for blue toys. This is like an ionic partition diagram.
In real life, atoms also have different types, just like your toys. Some atoms have electrons that they don't need, like how you may have toys you don't play with anymore. These atoms can give away or take in electrons to become more stable. When atoms do this, they become ions.
Now, imagine we draw a line in between the toy box for red toys and the toy box for blue toys. This line represents the ion exchange between two atoms. The ions on one side of the line are called cations (the ones that gave away electrons) and the ones on the other side are called anions (the ones that took in electrons).
In an ionic partition diagram, we draw a similar line to show the separation of cations and anions. The diagram helps us understand which ions will move to which side of the line when we put them in water or another solution.
So, just like how you organize your toys by color, scientists use ionic partition diagrams to organize ions by their charge and how they react in different environments.