Energy level diagrams Watch
I cant understand why the energy levels are represented in negative values. Hence the arrow shows increase in energy in that atom so as the energy increases the electrons move to higher energy levels and is 0ev the ground state if so when energy is given to the atom its emitting energy at the same time which doesn't make sense. I think I am missing an important point on this topic...
it's similar to the convention for gravitational PE in which energy increases to a maximum of zero which occurs at infinite separation of masses.
one benefit of the convention over saying ground state=zero is that you don't have a different zero for every type of atom.
When it is in the ground state in the atom, it is bound to the proton, and you need to give it energy (do work on it) to get it out of the atom. If you have to give it energy to get it out of the atom where its energy is zero, then by definition, its energy when in the atom is negative.
It's potential energy that can be negative because the zero of potential energy can be chosen to be anywhere. It's only changes in potential energy that really matter. Does it get greater or less.