<p>Okay, I AM NOT asking you to do my homework (the answers are already in the back of the book). What i really want is for someone to explain to me why the answers are correct.</p>
<p>Problem:</p>
<p>Give the max. number of electrons in an atom that can have these quantum numbers:</p>
<p>a) n = 4 [answer = 32]
b) n = 5, ml = +1 [answer = 8]
c) n = 5, ms = +1/2 [25]
d) n = 3, l = 2 [10]
e) n = 2, l = 1 [6]</p>
<p>You don't have to explain each problem, but how do I figure this out? I've tried, unsuccessfully, to figure it out myself, but i'm stuck (even though i've read the chapter).</p>
<p>and again, I AM NOT asking you to do my homework (i already have the answers), but I would sincerely like for someone to explain to me how to do this (my teacher is no help).</p>
<p>I'm not sure if this is a good explanation... but...
a. The quantum numbers are divided into n, l, ml, and ms (it is more like n-->l-->ml-->ms in that order). (I assume u know what they stand for and their properties) So the max number of electrons in a atom that has a principal quantum number of 4 would be:
When n= 4, l can be 0,1,2,3,
When l=0, m1=0
When 1=1, ml=-1, 0, 1
When l=2, ml=-2, -1, 0, 1, 2
When l=3 ml= -3, -2, -1, 0, 1, 2, 3
ms will always be either -1/2 or ½</p>
<p>so count the number of electrons would be all the “ml’s” x 2 (because of the -1/2 and ½ spin)=16x2= 32</p>
<p>b. When n=5 ml=+1
so when n=5, l can be 0,1,2,34
Since the problem said ml=+1 only on 4 level of l where ml can be +1
That would be when l=1,2,3,4, and only once does the ml=+1 appear in each of the "level" of l. Also in each ml=+1 there can be 2 spins (1/2 and -1/2) therefore, 4x2=8</p>
<p>The problems is basically saying how many of the electron meets the criteria that they listed...</p>
<p>b) n = 5, ml = +1 [answer = 8]
c) n = 5, ms = +1/2 [25]
d) n = 3, l = 2 [10]
e) n = 2, l = 1 [6]</p>
<p>b) l=0: ml=0 => 0e with ml=+1
Now count down l and when ml=+1 multiply the number by two (because of the spin)
l=1: ml= -1,0,1 => 2e
l=2: ml= -2, -1, 0, 1, 2 => 2e
l=3: ml= -3... 0, 1 => 2e
l=4: ml= -4...0,1 => 2e
2x4=8e (e=electron)</p>
<p>You just have to write everything from l to ms and count down the electrons, keeping in mind the order, and the fact that ms=+1/2 comes first (that's why you get 25 electrons at c) ). Soon you'll find it really easy to deal with. Quantum Chem can be fun once you understand it.</p>