What Quantum Numbers Define a Hydrogen Atom's State with No Angular Dependence?

In summary, the quantum numbers used to define the state of hydrogen are n, l, and m, with n representing the energy level, l representing the eigenvalues of total orbital angular momentum, and m representing the z component of orbital angular momentum. The wavefunction for this system has no angular dependence and can be written as ##\sqrt{\frac{1}{4\pi}}u_n^0##, where n can be any integer, l is equal to 0, and m is equal to 0. The term "spatial part" is used to distinguish it from the spin part, but for the purposes of this exercise, the spin is not considered. Therefore, the values for all angular momentum quantum numbers for the
  • #1
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Homework Statement



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What quantum numbers are used to define state of hydrogen? The wavefunction has no angular dependence. Find the values of all the angular momentum quantum numbers for the electron.

Homework Equations


The Attempt at a Solution



The numbers are n, l and m.

n: Energy level
l(l+1): Eigenvalues of total orbital angular momentum
m: z component of orbital angular momentum

The complete wavefunction is given by: ##\psi = u_n^l Y_l^m##.

Thus the only spherical harmonic that doesn't have angular dependence is ##Y_0^0 = \sqrt{\frac{1}{4\pi}}##.

Thus the wavefunctions are ##\sqrt{\frac{1}{4\pi}}u_n^0##.

Thus n = any integer, l = 0, m = 0.

I'm slightly bothered by the term 'spatial part' of the wavefunction.
 
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  • #2
"Spatial part" as opposed to "spin part". The exercise probably doesn't want you to worry about spin (my guess -- change that if you just finished a chapter on spin...)
 
  • #3
BvU said:
"Spatial part" as opposed to "spin part". The exercise probably doesn't want you to worry about spin (my guess -- change that if you just finished a chapter on spin...)

We learn about the gross structure of Hydrogen, which ignores spin as the Hamiltonian is the KE of the nucleus and electron, and the potential energy.

Are my answers right then?
 
  • #4
I would say yes. A nitpicker would argue n isn't a quantum number for angular momentum. In that case the answer is: l = 0 and m = 0
 
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  • #5
In general the wavefunction is a function of space and time, but I assume you mean the part that depends only on the spatial coordinates. In that case, the wavefunction for the hydrogen atom is a product of the radial wavefunction and the spherical harmonic, which represents the angular part. The radial wavefunction is dependent on the principal quantum number, n, while the spherical harmonic is dependent on the angular momentum quantum numbers, l and m.

To find the values of all the angular momentum quantum numbers for the electron, we can use the following rules:

1. The principal quantum number, n, can take on any positive integer value.

2. The angular momentum quantum number, l, can take on values from 0 to n-1.

3. The magnetic quantum number, m, can take on values from -l to l.

Therefore, for the electron in a hydrogen atom, the possible values for l are 0, 1, 2, ..., n-1, and the possible values for m are -l, -l+1, -l+2, ..., l-2, l-1, l.

In the case of the wavefunction having no angular dependence, as stated in the problem, it means that l = 0 and m = 0. This corresponds to the s orbital, which is spherical in shape and has no angular dependence. Therefore, the only possible angular momentum quantum numbers for the electron in this case are l = 0 and m = 0.
 

FAQ: What Quantum Numbers Define a Hydrogen Atom's State with No Angular Dependence?

What is a wavefunction?

A wavefunction is a mathematical function that describes the quantum state of a particle, such as an electron, in terms of its position and momentum. It represents the probability of finding the particle in a particular state at a given time.

How is the wavefunction of hydrogen calculated?

The wavefunction of hydrogen is calculated using the Schrödinger equation, which takes into account the potential energy of the electron and the forces acting on it. The solution to this equation is a set of mathematical functions known as wavefunctions, which describe the probability of finding the electron at different energy levels and positions in the hydrogen atom.

What is the significance of the wavefunction of hydrogen?

The wavefunction of hydrogen is significant because it provides a complete description of the behavior of the electron in a hydrogen atom. It allows us to calculate the energy levels and probabilities of different states, which are essential for understanding the chemical and physical properties of hydrogen and other atoms.

How does the wavefunction of hydrogen relate to the uncertainty principle?

The wavefunction of hydrogen is related to the uncertainty principle, which states that it is impossible to know both the position and momentum of a particle with absolute certainty. The wavefunction represents the probability of finding the electron in a particular state, and the uncertainty principle tells us that the more precisely we know its position, the less precisely we can know its momentum, and vice versa.

Can the wavefunction of hydrogen be visualized?

No, the wavefunction of hydrogen cannot be directly visualized because it is a mathematical function that exists in a multidimensional space. However, it can be represented graphically as a three-dimensional probability distribution, which shows the likelihood of finding the electron at different positions in space. This visualization is known as an orbital and is commonly used to represent the wavefunction of hydrogen and other atoms.

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