An orbital is not an orbit, and the electron does not run along any drawn path. The cloud here is thousands of dots, each one a place the electron could have been caught, and it is densest where |ψ|² is largest. The shape follows the quantum number l: s is a sphere, p a two-lobed dumbbell, d a four-lobed cloverleaf, while 2s hides a hollow nodal shell inside. Each subshell holds 2l+1 orbitals and each orbital at most 2 electrons, and the energy ordering is why 4s fills before 3d.
An orbital is not an orbit, and the electron does not run along any drawn path. The cloud here is thousands of dots, each one a place the electron could have been caught, and it is densest where |ψ|² is largest. The shape follows the quantum number l: s is a sphere, p a two-lobed dumbbell, d a four-lobed cloverleaf, while 2s hides a hollow nodal shell inside. Each subshell holds 2l+1 orbitals and each orbital at most 2 electrons, and the energy ordering is why 4s fills before 3d.
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