Electron Configuration | Interactive Chemistry model

Interactive configuration

Element

Occupied shells

Total electrons

Orbital occupancy

Teaching note: Accepted ground-state exceptions are included for important transition and f-block elements. Shell totals group electrons by principal quantum number n.

How Does Electron Configuration Work?

Electron configuration describes how electrons are arranged around an atom. Electrons occupy shells, subshells and orbitals according to their energy levels.

Enter an atomic number in the interactive model to explore how electrons are distributed among the available orbitals and see how the electron configuration changes between elements.

atomic_no = 8

order = [
 (1,"s",2),(2,"s",2),(2,"p",6),
 (3,"s",2),(3,"p",6),(4,"s",2),
 (3,"d",10),(4,"p",6),(5,"s",2),
 (4,"d",10),(5,"p",6),(6,"s",2),
 (4,"f",14),(5,"d",10),(6,"p",6),
 (7,"s",2),(5,"f",14),(6,"d",10),
 (7,"p",6)
]

remaining = atomic_no
configuration = []
shells = {}

for n, sub, capacity in order:
    if remaining <= 0:
        break
    e = min(remaining, capacity)
    configuration.append((n, sub, e))
    shells[n] = shells.get(n, 0) + e
    remaining -= e

print("Configuration:", configuration)
print("Electrons per shell:", shells)

# Example: Oxygen, Z = 8
# 1s2 2s2 2p4
# Shell 1 = 2
# Shell 2 = 6

# Note:
# Cr, Cu, Nb, Mo, Ru, Rh, Pd, Ag,
# Pt, Au and several f-block atoms have
# ground-state exceptions to the simplest
# Aufbau filling sequence.

Electron Configuration Python Model

This Python model generates an electron configuration from the atomic number of an element. Change the atomic number and compare the calculated electron arrangement with the interactive chemistry simulation above.