Summary - Unit 2 - Bonding and Structure

BONDING AND STRUCTURE

of attraction
IONIC BONDING-strong electrostatic force

ions
between oppositely charged between
wo
COVALENT BONDS-strong electrostatic attraction

doesn't show




tions
me are mobile of electrons between then
nuclei and the shared pair
edge of the ion
↑ live aion is no Of e-
energy
f
-
more
shared
difficult to measure Hive carion required stronger force sum of atanic




Fedva
↑
ionic radius
f smaller ions i



cathode ↑ -
mode
of attraction
e
repulsion between
the
pairs surrounding
I
-


electron properties of - central arou

shape


ausing
a
<
migrain high charge
high melting >
-

greater e-density -
· >
electrons
- points Y
IONIC between
:

strength

↑ apans
increased change
↓ BUNDING densing shared e-pair come from




am doubeasa
only one of the banding
e-density falls to zero
tive ions are smaller aroms
between ions
EVIDENCE FOR - t
f
IONS
Y
Ioni than their dative covalent
RADII
separate
7 - - banding
arans
L ↳ e
. Als
+
.

g
t greater band
!
physical N3-
↳ ordinary
high melling
increases down
strength COVALENT shape
I properties me group
↓
Oneless
,
five ions are
BONDING




!
!
points
-




examples
same shape




/
↓
S
larger than their
Pi and Signa -
a
↓
smong attractice
E




- banding
atoms ~

nuclear
brittle ↓ electrostatic force
iOnS W


↓ no e-) no. protons
of attraction
increases
2

Pitt bonds
sigma 6
.




small force
ion ↓ ↓ bands
↓
can't conduct
e .

g .


moving one
held
↓
ions are
diameter respective to pull of nucleus overlap of p-orbitals
electricity are shared more
closely and
AlCI + AlC >
-
AlzCs
another layer over more
orbitals lying above
when solid overlap of dimer
↓ e- below the ceries of

↓ lying between the


ionsle
I -
arons




8
like charges centres of atoms
less attraction
will be adjacent 6
Der e-
SS
fixed and repel
0 + 0 - 00
conduct S P 6
-
act arlita
F-
when molten or 0 + os
dissolved
& +-
p6
-
↓
overlappinone To*



ELECTRONEGATIVITY-ability
in a covalent bond
of an atom to attract the
bonding o · Al




higher
boilinga



↑
Y
I
I
↓ shielding
stronger than
↓ valence e-
London forces
distance
from



↑
the

nucleus
between
polar molecules

&
M
asymmetrical
- -
act in PERMANENT
addition to
no. protonst
-
DIPOLE-DIPOLE FORCES I D
London e .
.
g
atomic radiit closer valence
e- are
FX --- H FT
H
-




forces
-



to the nucleus -
⑧
- ①
-




↓ ALWAYS pais
show lone




significant difference

POLARITY nelectronegativity

LON




n
active &
sep



the angle between a
covalent bond is always
POLAR COVALENT BOND -


unequal 1800
distribution of e-in bond
a
creating

g
charge separation (dipole Must have
a occur betw
available love simple
pair of e-

↑ alcohols,
carboxylic
between H acids , proteins and ,


and , F , 0
N < HYDROGEN >
- anides can all
SYMMETRICAL MOLECULES :

f BONDING
H-band


dipoles
-of individualbond
conco use 2
g NU3 He O HE
higher
. .
,


~
,



.
e
. polar (Cly
g
us non-polar Ch3( water ca
I chance of
t
form t o hydrogen can cause
anomalously dipoles to

bonds per high boiling points

Fo
Molecule


↓ paise-
lane ↓ I
in ice molecules general
hydrogen bonds act
are held
further increase
in addition
Lo
apart by hydrogen
bonds ↓ Landon forces

& more e-
low
density
↓
METALLIC BONDING-strong electrostatic attraction between
increased
metalians and delocacised e- London forces



↑ delocalised
strength
require lots of ↑ protons strength A
&
M
energy to break no .
of decocalised
e-per alon
no of
↑
.




protons
the less soluble
↑
bands
strong electrostatic form new
it is in wave

size metal ions and bands