Question

Name the following

Arrangement of electrons in different energy shells around the nucleus of an atom.

Answer 1

• The electronic configuration of an element describes how electrons are distributed in its atomic orbitals.
• The electrons are filled in the increasing number of shells viz. K,L,M,N,etc.
• Number of electrons in a shell is given by 2n² where n is the number of shells.
• Putting n=1,2,3 and 4, we get the number of electrons 2,8,18,32 that can be filled in each shell respectively.
• Let us take the example of aluminum.
• The atomic number of aluminum is 13.
• 2 electrons will fill the first shell i.e., the K shell.
• 8 electrons will fill the second shell i.e., the L shell.
• 3 electrons will enter the third shell i.e., the M shell.
• The electronic configuration of aluminum will be 2,8,3.

Hence, the answer is electronic configuration.