Atomic Structure Flashcards
Name fundamental particles
Proton neutron electron
Isotope definition
Atoms with the same n.o of pro but diff n.o of neut
why do isotopes have the same chemical properties
same number of electrons
What are electrons arranged into
Principle energy levels
Sub shells
Orbitals
Define principle energy level
The main energy level occupied by electron
Sub shell def
A group of atomic orbitals of the same type within a shell. Split into S P D F dep on location
Orbital def
Sub shells are further split into orbitals that can contain up to 2 e- with opposite spins
(Up ward and downward arrows)
How many sub shells in each principle energy level
n=1 ——> 1s
n=2 —> 2s, 2p
n=3 —> 3s, 3p, 3d
n=4 —> 4s, 4p, 4d, 4f
Periodic table is divided into blocks. What does the block of an element dep on
The sub shell that the outermost electrons are in
How is the periodic table organised and where are the blocks
S block : group 1 + 2
D block: middle section (transition metals)
P block : right of table starting from group 3
Info about s orbital found in s subshell
Spherical shape
Can hold up to 2e-
P orbital
3 p orbitals x,y,z
2 e- each
So subshell holds 6 ELECTRONS
Dumbbell shape
D orbital
5 d orbitals with 2e- each
10 ELECTRONS TOTAL
Order of energy levels from high energy to low
S has the Lowest followed by P then D
Always fill from lowest to highest
What’s special ab 4s subshell
Fills before 3d subshell bc it’s lower in energy
Order of filing up shells
1s, 2s, 2p, 3s, 3p, 4S!!, 3d, 4p, 4d,4f
What is important to remember about filling up orbitals w the same energy eg: three 2p orbitals (xyz)
We put e- into individual orbitals before we pair them
Why are chromium and copper execeptions?
The 3d sub level is more stable when half of completely full so in the case of chromium by having only 1 e- in 4s sub level it can have a half full 3d subshell.
Expected config: …3d4 4s2
Actual: ….. 3d54s1
Short hand version of electronic configuration
Look at noble gas before hand and write tagt first eg sodium would be (Ne) 3s1
What is different about the elements in the d block in terms of configurations for ions and why
When d block elements loose e-
They are lost from the 4s sub shell before the 3d sub shell
- once the 4s subshell contains e- it has a higher energy than the 3d sun shell
First ionisation definition
Energy needed to remove one mole of electrons from one mole of atoms in their gaseous state to form 1 mole of 1+ ions (also in gaseous state)
Second ionisation energy definition
Energy needed to remove one mole of electrons from one mole of 1+ ions in their gaseous state to form 1 mole of 2+ ions also in their gaseous state
Successive ionisation energies
Continual removal of e- and measuring ionisation energy each time
Equations for ionisation energy of mg
First ionisation energy: mg -> mg+ + e-
Second : mg+ -> mg2+ + e-
Third: mg2+ -> mg3+ + e-
Fourth: mg3+ -> mg4+ + e-
Fifth: mg4+ -> mg5+ + e-
(All should have (g) )