Question

the electronic configuration of an atom an element with atomic number 10 is...
1s²2s²2p⁴
1s²2s⁶
2s²2p⁶
1s²2s²2p⁶

Explanation:

The atomic number is equal to the number of electrons in a neutral atom. For an atom with atomic number 10, we fill the electron - orbitals following the Aufbau principle. The first energy level (n = 1) has one s - orbital which can hold 2 electrons (1s²). The second energy level (n = 2) has one s - orbital that can hold 2 electrons (2s²) and three p - orbitals that can hold a total of 6 electrons (2p⁶).

Answer:

1s²2s²2p⁶