We've just started learning about ψ in the quantum mechanics section of our atomic structure chapter. So while reading, I found these graphs where they used certain units along the y-axis for the graphs for ψ and radius (in nm), and ψ^2 and radius. What units are these exactly??? My chemistry teacher wasn't able to give a reasonable explanation, and trying to learn about it online has left me overwhelmed with all sorts of complicated formulae. So please help, and don't forget: this is the first time I'm reading about all this.