2.2.2 Sub-shells and energy levels Flashcards
how are orbitals organised in a shell?
within each shell, orbitals of the same type are grouped together to form a sub-shell
what does a sub shell contain?
orbitals of only one type
how do electrons occupy subshells
in order of increasing energy levels
what is the Aufbau Principle?
the rules to figure out electronic configuration
what are the rules of the Aufbau Principle?
-electrons are added one at a time
-the lowest energy level is filled first
-each energy level must be full before the next begins to fill
how are sub-shells filled?
each orbital is filled singly, before pairing starts (sitting on a bus rule)
which orbital is a lower energy level, 4s or 3d
4s orbital is a lower energy level than 3d orbital
which sub-shell fills first?
the orbital with the lowest energy level (closest to the nucleus)
what is electron configuration?
the arrangements of electrons in an atom or ion
how can you figure out electron configuration?
using the Aufbau Principle
what is the formula for electron configuration?
nx^y
what does the n stand for in nx^y?
shell number
what does the x stand for in nx^y?
type of orbital
what does the y stand for in nx^y?
number of electrons in the orbitals, making up sub-shells
which electrons are lost/gained first if an atom is ionised to become a positive ion?
the electrons found in the highest energy levels are lost first
how will the electron configuration change, if the atom becomes a positive ion?
it will show fewer electrons at the highest energy levels
which electrons are lost/gained first if an atom is ionised to become a negative ion?
the electrons gained will continue to fill the sub-shells as the other electrons did
what is the electron configuration of nitrogen?
1s^2 ,2s^2 ,2p^3
what is the shorthand electron configuration of chlorine?
[Ne] 3s^2, 3p^5
how to do shorthand electron configuration?
go to noble gas previously in the periodic table, place in square brackets and do regular configuration for the remainder
exam question: how many full orbitals are in an atom of sulfur? (using 1s^2, 2s^2, 2p^6, 3s^2, 3p^4)
7
instead of “it formed a full outer shell”, what should you say?
it formed a negative/positive ion, depending
