Which among the following shell is at the highest energy level?
Each of the shells is associated with a fixed amount of energy.
An electron present in the first or the K shell, possess the least amount of energy. The shells nearer to the nucleus have less energy as the force of attraction between the nucleus and the electrons is maximum.
The distance of shells from the nucleus follows the order: K < L < M < N
The force of attraction decreases with increasing distance from the nucleus.
Therefore, N shell has maximum energy associated with it as it is the farthest.