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### QUESTION 1D.23 FROM HW

Posted: Thu Oct 17, 2019 12:01 am
"How many orbitals can have the following quantum numbers in an atom:(a)n=2,l=1;(b)n=4,l=2,ml=-2; (c)n=2;(d)n=3,l=2,ml=+1?"

Can someone help me with this question? Thank you.

### Re: QUESTION 1D.23 FROM HW  [ENDORSED]

Posted: Thu Oct 17, 2019 10:51 am
a) n=2, l=1 indicates a 2p orbital with 3 different orientations. (3 different orbitals)
b) n=4, l=2, m=-2 indicates a 4d orbital with a single orientation. (1 orbital)
c) n=2 indicates the 2s orbital with a single orientation, and a 2p with 3 different orientations. (4 different orbitals)
d) n=3, l=2, m=+1 indicates the 3d orbital with a single orientation. (1 orbital)

### Re: QUESTION 1D.23 FROM HW

Posted: Thu Oct 17, 2019 3:41 pm
For A, n=2 means we're looking at the second shell. And l = 1 means we're looking at a p orbital. Because the magnetic quantum number is not specified, we don't know the orientation. This means that it could be any of the three p orbitals. Therefore, 3 orbitals can have these quantum numbers.

For C, given only n=2 means all we know is that we are looking at the second shell. In the second shell, we have one s orbital and 3 p orbitals. Therefore, 4 orbitals can have this quantum number.

For B and D is 1 because they both have 3 quantum numbers that identify 1 orbital