Calculadora de Configuração Eletrônica

The Electron Configuration Calculator is an online tool that distributes electrons of a neutral atom into the K, L, M, N, O, P, and Q shells following the Aufbau principle (filling in order of increasing energy). The simplified model uses classic maximum capacities: K (2 electrons), L (8), M (18), N (32), O (32), P (18), and Q (8), based on the Linus Pauling diagram. Simply enter the atomic number (Z) and the calculator fills the shells until all electrons are placed, respecting each shell's limit.

How it works: the calculator receives the atomic number (equal to the number of electrons in a neutral atom) and, for each shell, checks how many electrons it can hold (K up to 2, L up to 8, etc.). It allocates electrons sequentially: first fills the K shell, then L, and so on, until all electrons are distributed. If the number of electrons exceeds the capacity of the last shell, the remainder goes to the next available shell. The output shows the shell distribution (e.g., 2, 8, 18, 4) and the full electron configuration in energy order (e.g., 1s² 2s² 2p⁶ ...).

When to use: this calculator is helpful for chemistry students who need to understand atomic electron structure, predict periodic properties (such as atomic radius, electronegativity), or write electron configurations quickly. It is also valuable for teachers demonstrating shell filling in the classroom, or professionals working with spectroscopy or basic quantum chemistry. Avoid using it for ions (charged atoms) without adjusting the electron count.

Cautions: the simplified model does not consider subshells (s, p, d, f) or exceptions to the Pauling diagram (such as chromium and copper). For precise configurations with subshells, use a more detailed calculator. Also, note that the maximum capacity of outer shells (O, P, Q) is theoretically limited, but in practice, atoms with many electrons may have different configurations. Always ensure the atomic number entered corresponds to a neutral atom.