Answer:
From n = 2 to n = 1
Step-by-step explanation:
There are 7 energy levels, numbered from 1 to 7, and in which electrons are distributed, logically in order according to their energy level. Electrons with less energy will be spinning at level 1. Level 1 is the innermost level or closest to the nucleus and is the one with the lowest energy level. Level 7 is the outermost or furthest from the core and is the level that has the highest energy level.
Then the electrons are spinning around the nucleus forming layers, as previously mentioned. In each of them, the energy that the electron possesses is different. In the layers very close to the nucleus, the force of attraction between it and the electrons is very strong, so they will be strongly bound (joined). The opposite occurs in remote layers, in which electrons are weakly bound, so it will be easier to make electronic exchanges in the last layers.
So, since electrons are more strongly attracted to the nucleus, for an electron to jump from the fundamental state at level n = 2 to level 1, a lot of energy is required to overcome the aforementioned force of attraction. At the other levels, the attraction of the nucleus is lower, so the energy required to jump to other energy levels will also be lower.