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Atoms and the Periodic Table

In the **Bohr Model**, electrons can move up and down to different orbitals or shells based on absorbing or releasing of energy.

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Bohr Model (Simplified) Concept 1

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in the Bohr model of the atom, electrons travel around the nucleus in circular orbits called shells. Now these shells use the variable end and they're just a grouping of electrons surrounding the nucleus that ties into their potential energy. Now, potential energy itself is the energy and object possesses in this case the electrons based on its given position. So depending on what shell the electron is found in will have varying potential energies. So here we take a look at boards model of the atom. We have our adam here remember our and variable is our shell deals with our shell or in this case shell number and also energy level. Because again it's a it's attached to potential energy. If we take a look here, we have our nucleus and in the nucleus we have our protons and neutrons. After that we have our first black circular orbit. This represents our first shell. The first show has an end value equal to one in this, shall we have two electrons, 12 And then the next black circular orbit. That's our second shelf. So and equals two. That one possesses 123 electrons. So that's the way we observe the atom based on boards model. Now, remember protons are the positively charged particles, neutrons are neutrals, electrons are the negatively charged. Once and again. Remember the nucleus itself possesses are protons and our nutrients. So just remember when we're talking about our adam, we have shells within these shells. We have basically electrons that move around in an orbit and based on which shell the electrons are found, Their potential energies can vary.

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Bohr Model (Simplified) Example 1

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What is the value of N for the electron furthest from the nucleus? Alright, so remember each black circular orbit is a shell. So here this one is our first shell, so and equals one. This here is our 2nd shell cell and equals two. This one here, this one here is our third shuttle and equals three. Remember that we're talking about the electron furthest away from the nucleus. Here is our nucleus, the electron that's furthest away from it is this electron. Here It is found in the 3rd Shell, where n equals three. So that means that option A would be the correct answer for this example question.

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Bohr Model (Simplified) Concept 2

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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.

**Absorption** occurs when electron absorbs energy and jumps to higher energy state.**Emission** occurs when electron emits energy and falls back down to lower energy state.

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Problem

Which of the electron transitions represents an example of absorption?

A

n = 5 to n = 3

B

n = 1 to n =3

C

n = 6 to n = 2

D

n = 7 to n = 4

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Problem

Which of the electron transitions represents an example of emission?

A

n = 2 to n = 4

B

n = 3 to n = 6

C

n = 3 to n = 1

D

n = 4 to n = 7

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Problem

Which of the electron transitions represents an example of absorption with the greatest energy?

A

n = 1 to n = 4

B

n = 2 to n =3

C

n = 6 to n = 7

D

n = 5 to n = 6

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