Which electron configuration represents a potassium atom in excited state

The electronic configuration of potassium atom in excited state is

Explanation:

There are 2 states classified under energy levels:

1. Ground state: This is the lower energy state which is termed as stable state.

2. Excited state: This is the upper energy state and is termed as the unstable state. All the electrons which are present in this state always come back to the ground state.

Ground state electronic configuration of potassium (Z = 19) :

As, only 1 electron can freely move to upper state. Hence, the excited state electronic configuration of potassium will be: