now within a given Adam. We confined electrons within given orbits or shells, but realize through either the absorption or mission of energy, electrons are able to move between these different shells. Now, when we talk about absorption and emission, what exactly do we mean? Well, when we say absorption, this is one electron moves from a lower numbered shell toe are higher numbered shell, and the mission is when the electron does the opposite. It's one electron moves from a higher number of shell to a lower numbers show every word to visually see this. Here we have absorption in the first image. Here in absorption. We're going to say the electron absorbs energy, So basically, we have some outside energy source displayed as this energetic photon. That photon is giving its energy to this electron. This electron is initially in the first orbit of the atom, so it's in shell one. It absorbs this energy, and it allows it to a jump upto a higher energy state, which we call the excited state. So this electron is able to, in this example, go from the first shell to the third shell. Now, if absorption is going up to a higher level. Emission is the opposite here realize that that electron can't hold on to that outside energy forever. Eventually it has to let it go. So here the electron emits or what we say releases this excess energy it got from earlier. When it does so, it's gonna fall back down to its original position, which we call its ground state. So here the electron goals from the third shell and goes right back down to its initial position, which is shell one. But how does this relate? How hard is it for electrons to travel between these shells? Well, here we talk about energy transitions were saying here, As the shell number increases, the distance between them is going to decrease. So if you look, this is shell 1234 and five. The distance between shells one and two is this big distance. Here. The distance between two and three is this is this is between four and five. Is this and then you can see that the distance is getting smaller and smaller. The higher up we go in terms of shell number. That's because as the distance traveled by an electron is increasing the than Mawr energy is needed, the energy increases. So basically, what we're saying here is that traveling between shells one and two requires the most energy look at the distance. It has to travel from here all the way up to here. And if we wanted to go from shell, one is shell three. That's an even bigger cost. If you're trying to go from Shell one, all we have to shell three. Look how much bigger the distances. But then, as we're starting up at a higher shell number, less energy is required. So let's say we wanted to go from Shell 3 to 5. Not as much energy is required. So just realize that distance equals energy. The more electron has to travel in the greater amount of energy is needed and realize. Here is the shell number increases than the distance between the shells get smaller. So it's easier front electron to go from, Let's say, shell six to Shell seven than it is from going from shell one to shell, too.