9. Quantum Mechanics
Bohr Model
Struggling with General Chemistry?
Join thousands of students who trust us to help them ace their exams!Watch the first video
Video duration:
2mRelated Videos
Related Practice
Skip to main content
Now in the Bohr model of the atom, electrons travel around the nucleus in circular orbits, which we call shells. Now these shells use the variable n and a shell is just a grouping of electrons surrounding the nucleus that ties into their potential energy, so their energy of position. We're gonna say associated with Bohr's model is what we call the Rydberg constant. And when it's dealing with joules, the value is 2.178 times 10 to the negative 18 as the value for Rydberg constant. Now if we're looking at Bohr's model, remember in our Bohr's model we have our nucleus here in orange, and within the nucleus remember that's where we find our protons and our neutrons. Remember protons are positively charged, neutrons are negatively charged. Orbiting around the nucleus in these orbits or shells are our electrons. Remember, electrons themselves are negatively charged. And we're going to say, if we take a look, here's our nucleus, this is our first orbit or our first shell, so n equals 1. This is our second orbit where we find 3 more electrons, so this is shell 2, and this would be shell 3. And remember here we said shell uses the variable n, and we're gonna say n equals our shell number, but also what we call our energy level. We'll go in greater context in terms of that when we talk about the quantum numbers. Now if how do we tie this into the energy of a particular electron? Because remember, we said that the shell number ties into their potential energy. Well, we're going to say here, the energy of an electron within a specific shell can be determined by delta e or e n, which is the potential energy of an electron, equals negative times r, which is our Rydberg constant, which we said is 2.178 times 10 to the negative 18 joules, and that's gonna be times z squared over n squared. Z here equals the atomic number of an element. For example, hydrogen, first element on the periodic table has an atomic number of 1. And then n squared on the bottom, remember n would just be the shell number or energy level for that particular electron. So just remember, electrons travel within orbits around the nucleus, and by using this potential energy formula you can determine the potential energy associated with any particular electron within a given atom.
01:21
