Question

Which of the following sets of quantum number could describe one of its highest energy electrons in Ti, and why
a) n=3, l=2, ml=2, ms= -.5
b) n=4 l=1, ml=0, ms=.5

Answer 1

a) n=3, l=2, ml=2 amd ms=-.5 is the right answer

Answer 2

can someone explain?
a is 3d , b is 4p
isn't 4p higher energy then 3d?

Answer 3

it is as you said, in a general case. But Titanium is a transition metal.

Answer 4

Please read the following for clarification
http://www.scienceclarified.com/everyday/Real-Life-Chemistry-Vol-1/Transition-Metals-How-it-works.html

Answer 5

the question asks for "one of its highest energy electrons", so we look for the highest energy orbitals in titanium that are occupied by electrons.

assume we are talking about the ground electronic state of the titanium atom. the electronic configuration is [Ar]3d^24s^2. the 4s and 3d orbitals are occupied, but the 4p orbitals are not occupied.

the choices you were given are:

a) n=3, l=2, ml=2, ms= -.5, a spin-down electron in a 3d atomic orbital
b) n=4 l=1, ml=0, ms=.5, a spin-up electron in a 4p orbital.

since the electronic configuration of Ti has the valence electrons in the 4s and 3d subshells, one of the highest energy electrons can be found in the state described by choice a.

however, electrons will not be found in the state described in choice b because the 4p subshell in titanium is unoccupied. we are assuming of course that the titanium atom is not in an excited state.