Do phosphorus and sulfur have d orbital electrons?
The teachers manual for Addison-Wesley's Chemistry on page 428
states that P and
S have d orbital electrons. Also, it says that
NO3-,OH-, and SO3 are
diamagnetic while H20 is paramagnetic.
Would not NO3- have a single unpaired
electron? Would not OH- also have just one unpaired electron? I
can see that
SO3 would not have a single unpaired electron. I would agree
that H20 does not
have a single unpaired electron.
DISCLAIMER: I have not seen the reported items in the
Addison-Wesley teachers' manual for Chemistry. My answer addresses
the accuracy of the statements quoted above, and does not necessarily
disparage Addison-Wesley's textbook, which I have not seen.
Most of the statements above are either false or misleading.
- In the ground state, phosphorus and sulfur do
not have occupied d atomic orbitals. However, d-orbital
hybridization is often invoked to explain the fact that these elements can
form more than the usual number of bonds, such as PF5 or
H2SO4.
d-Orbital hybridization is an inadequate model of bonding in such
molecules. See this
MadSci answer, as well as L. Suidan, J.K. Badenhoop, E.D. Glendening,
and F. Weinhold, "Common Textbook and Teaching Misrepresentations of
Lewis Structures," Journal of Chemical Education, 72,
583 (1995). Thank you to Eric
Scerri for the second reference.
- Water is not paramagnetic; it is diamagnetic.
In fact all of the molecules and ions cited above (nitrate, hydroxide,
sulfur trioxide, water) are diamagnetic.
- If you draw correct Lewis structures for the cited molecules
and ions, you will find that all electrons are paired. This is supported
by quantum mechanical calculations. But nitrogen trioxide (or hydroxyl
radical) should be paramagnetic, because it has a single unpaired electron.
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