Question

Write the electronic configuration of an element having atomic number equal to 11.

Answer 1

Answer:

The element with an ‘atomic number’ of 11 is sodium.

The electron configuration of sodium (Na) is:  $15^{2} 25^{2} 2 p^{6} 3 s^{1}$

Explanation:

• Since the ‘atomic number’ is 11, sodium will have 11 protons and 11 electrons.
• These 11 electrons are “present in its orbitals” surrounding the nucleus.
• The first 1s orbital holds two electrons; the second 2s holds two electrons; third 2p orbital can hold 6 electrons; the last 3s orbital can hold 1 electron.
• The last 1 electron becomes its valence electron giving the valency of 1 to sodium.