CH 301 Worksheet 4
Dr. Sparks, Fall 2010
Things you should know:
•
Definition of cation (positively charged ionic species) and anion.
1. Give a brief explanation of each of the following quantum numbers in your own words: .
•
n = principal quantum number, the main energy levels, any positive integer.
•
l
= azimuthal quantum number, shape of orbits, subshell, 0 to n-1.
Numbers indicate s, p, d, f orbital shapes
•
m
= magnetic quantum number, orientation of orbital, -
l
to
l.
Tells you the number of individual orbitals
within one subshell.
•
s
= spin quantum number, direction of spin, +1/2 or -1/2 (NOTE: The value for this number does not
matter, just that there is a positive and negative value of equal magnitudes.)
2. True or False? The following set of quantum numbers is acceptable (0,0,0, +1/2). Explain.
False. The principal quantum number, n, corresponds to the volume of space in which an electron moves around a
nucleus and can only be positive integers. Therefore, 0 is not a principle quantum number.
3. How many electrons can have the following quantum numbers in an atom:
n
= 3,
l
=2?
10 electrons. For every subshell (
l
) there are -
l
to
l
possible orbitals (here, -2, -1, 0, 1, 2), each of which may contain
two electrons with opposite spins.
4. State in your own words the Pauli exclusion principle. Which of the quantum numbers is it
most concerned with?
In a given atom, all of the electrons must be described by a unique set of four quantum numbers (n, l, ml and ms). It