# QuantumNumbers-Chem

• Apr 18th 2010, 05:43 AM
quantumie
QuantumNumbers-Chem
I studied quantum numbers and learned the formula and concept but when I'm answering the questions in my book, I'm really confused..Please help me..

This is my problem:

Which of the ff sets of quantum number is allowable?

a) n=4, l= 2, ml= 0
b) n=3, l=2, ml= -1
c) n=5, l=3, ml= -3
d) n= 3, l=0, ml=1

*when I start solving it, I was able to solve for b and d but I was confused on letter a and c... they say that the correct answer is letter a, b and c..

Here's my solution on letter a:

n=4

l= n-1
= 4-1
= 3
<but the set tells that l= 2>

ml= 2l + 1
= 2(3)+ 1
= 7 ( -3, -2, -1, 0 ,1, 2 3)

Here's my solution on letter c:

n= 5

l= n-1
= 5 - 1
= 4
<but the set tells that l = 3>

ml = 2l +1
= 2(4) + 1
= 9 ( -4 , -3, -2, -1, 0, 1, 2, 3, 4)

how could that happen??? is the formula changing from n-1 to n-2? i'm really confused plss help me...
I'm confused..pls help me...
• Apr 19th 2010, 01:04 AM
Haytham
Quote:

n=4

l= n-1
= 4-1
= 3
<but the set tells that l= 2>
l can be any from 0 to n-1 (not just n-1)
• Apr 19th 2010, 02:53 AM
quantumie
thanks a lot! sorry, I don't know how to do "E-Thank You" method here...