In Table 7.5, the pattern that develops with increasing n suggests that the number of different sets ofl,mlvalues for a given energy level n isn2. Prove this mathematically by summing the allowed values ofmlfor a givenlover the allowed values oflfor a given n.

Short Answer

Expert verified

The number of different sets ofl,ml values for a given energy level n isn2 .

Step by step solution

01

 Given data

Energy level = n.

02

 Approach to find the final answer

For each n that is the principal quantum number, l, which is the azimuthal quantum number, can be from 0 to n – 1; for each n, there are 2l+1 allowed values ofml.

03

 To prove the number of different sets of l,ml values for a given energy level n is n2

Summing all the allowed values ofml for a given l over the allowed values of l for a given n as:

0n-12l+1=20+n-12n+n=n-1n+n=n2-n+n=n2

Thus, the number of different sets ofl,ml values for a given energy level n isn2 .

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