Section A Flashcards
HSAB - Hard Soft Acid Base Theory
Hard acids prefer to bind to hard bases
Soft acids prefer to bind with soft bases
Factors that affect Hardness
Hard Acids - H+
Small + High Charge
Soft Acids - Cu+
Large + Small or neutral charge
Hard Base - F- , OH-
High Electronegativity
Soft Base - CN- ,I-
Low electronegativity
No. of e- at the central atom
No. of Valence e- at central Atom +
1 e- for each single Bond -
Overall charge on the compound
Finding the number of electron pairs
2
VSEPR
Total No. of e-
No. of Valence e- +
1 e- per single Bond -
Overall charge
VSEPR
No. of e- Pairs
2
Layout for VSEPR
Compound
Val e- =
Bonds =
Charge =
Total e- =
No e- pairs =
Describe the bond angle and how many pairs you have.
Name of the shape of molecule
Name the Shape of molecules
Linear
Trigonal Planar **Careful of orientation ** think of example = ClF 3
(lp and bp)
T- Shaped ##
Tetrahedral
Trigonal Bipyramidal
Octahedral
Seahorse shape* ask if we need this*
Square Based Pyramid *
Triangle Based Pyramid *
Square Planar *
Name the Shape of molecules
Linear
Trigonal Planar **Careful of orientation ** think of example = ClF 3
(lp and bp)
T- Shaped ##
Tetrahedral
Pyramidal
Trigonal Bipyramidal
Octahedral
Seahorse shape* ask if we need this*
Square Based Pyramid *
Triangle Based Pyramid *
Square Planar *
d - orbitals
Draw
Table P15
n - principle quantum number
l - orbital angular quantum number
ml - magnetic quantum number
n^2 - number of orbitals
Scan
Rule - 1
Aufbau Principle
Electrons are placed in the lowest available orbital first in sequence
Rule - 2
Pauli Exclusion Principle
No two electrons can have the same set of four quantum numbers meaning only two electrons can occupy an orbital with opposite spins
n, l, ml and ms
Rule - 3
####extra practice ###
Hunds first Rule
Degenerate orbitals are filled singly for as long as possible with parallel spins
Orbitals of the same energy = Looks exactly the same
They have the same “ms” Value for as long as possible
Rule - 3
####extra practice ###
Hunds first Rule
Degenerate orbitals are filled singly for as long as possible with parallel spins
Orbitals of the same energy = Looks exactly the same
They have the same “ms” Value for as long as possible
Extra Hunds first rule
Explaation
- Spin pairing energy
It takes energy to put 2 electrons into the same orbital - Spin exchange energy
is energy gained when two or more electrons can exchange positions with no change in electron configuration.
100kJ/mol
Spin exchange favours Filled anf half filled shells as you get the maximum possible spin exchanges.
Extra Hunds first rule
Explaation
- Spin pairing energy
It takes energy to put 2 electrons into the same orbital - Spin exchange energy
is energy gained when two or more electrons can exchange positions with no change in electron configuration.
100kJ/mol
Spin exchange favours Filled anf half filled shells as you get the maximum possible spin exchanges.
Electronegativity
Trend and how to work out
Top right = Biggest
Bottom left = Smallest
E > 1.7 (Ionic)
E
Electronegativity
def
The ability of an atom to attract a pair of shared electrons in a covalent bond.
