PERIODICITY
JI
"
"" " "" "" " "
f
""
idiot: Timm!:: energy
- "
.
e- is
3. 2. 1.2 .
TRENDS
atomicradivsdnecnreamen period across
-
e
-
added to same principal energy level
leg PD nuclear
charge 1
-
.
-
shielding by inner e SAME
-
-
-
-
i. e- in outer shell -
more
strongly attracted to nucleus
ionization
energy
increases across B nuclear
charge 9 without increase in
shielding
-
-
AR decreases O
attraction of outer
-
0
e in same
principal e-
stronger
-
-
-
-
i. harder to remove , more e
exception : (P 3 . . . & )
P2
① At ② P s
My
→
→
removed Al 3p P:
3p Hill S 3pmHit
-
:
-
e :
35
My paired e- repulsion i easier to remove
-
-
-
.
added
3p more shielded than 3s
stability half full full sub levels
-
or
-
:
less
energy to
i. remove
At lower 1st IE
melting point
I dependent on type of bonding & type of element
① Na → Al -
across period charge of cations 1
T
metallic
bonding of delocalised
-
no e
-
-
-
size of ion l
1
increased -
strength of metallic bond
NPT increases but Al not as much as
Mg
-
,
( has effect)
type of lattice
, PERIODICITY
3. 2. 1.2 TRENDS
c ) CD
.
Pg molecule Soo molecule 92 molecule Arm Ole cute
melting point
② si lots of covalent bonds
strong
-
very
-
macromolecular i.
high BPT -
lot of energy required
③ P metal Ar atoms
→ Ar -
non -
single
-
molecular (not Art -
limited HW's
-
diff sizes of molecules -
low BPTIMPT
Ar monatomic weak Vdw 's least amount of
energy explanation
-
-
:
-
Az stronger weak Vdw 's I Ar the electrons
-
lmore more than more
energy
e
-
-
-
,
Py e- stronger KW 's than Ar , 11 the stronger the Van
more more
energy
- -
-
-
( Tir: I
-
der Wall forces
G bigger molecules more e =
stronger Vdw 's most
energy
-
-
,
i.
higher MPTIBPT
electronegativity
trend :
across period inweasesm explanation :
more
pt in nucleus
smaller AR
change shielding
-
more e i no in
electrical
conductivity
trend : Na ,
Mg ,
Al -
good conductors explanation :
conductivity increases Na AL Na Al -
→
-
Si -
semiconductor
.
metals
conductors of the de localised electrons
None of the rest conduct
electricity
'
cos
rest
-
simple molecular
free electrons
no
moving
•
JI
"
"" " "" "" " "
f
""
idiot: Timm!:: energy
- "
.
e- is
3. 2. 1.2 .
TRENDS
atomicradivsdnecnreamen period across
-
e
-
added to same principal energy level
leg PD nuclear
charge 1
-
.
-
shielding by inner e SAME
-
-
-
-
i. e- in outer shell -
more
strongly attracted to nucleus
ionization
energy
increases across B nuclear
charge 9 without increase in
shielding
-
-
AR decreases O
attraction of outer
-
0
e in same
principal e-
stronger
-
-
-
-
i. harder to remove , more e
exception : (P 3 . . . & )
P2
① At ② P s
My
→
→
removed Al 3p P:
3p Hill S 3pmHit
-
:
-
e :
35
My paired e- repulsion i easier to remove
-
-
-
.
added
3p more shielded than 3s
stability half full full sub levels
-
or
-
:
less
energy to
i. remove
At lower 1st IE
melting point
I dependent on type of bonding & type of element
① Na → Al -
across period charge of cations 1
T
metallic
bonding of delocalised
-
no e
-
-
-
size of ion l
1
increased -
strength of metallic bond
NPT increases but Al not as much as
Mg
-
,
( has effect)
type of lattice
, PERIODICITY
3. 2. 1.2 TRENDS
c ) CD
.
Pg molecule Soo molecule 92 molecule Arm Ole cute
melting point
② si lots of covalent bonds
strong
-
very
-
macromolecular i.
high BPT -
lot of energy required
③ P metal Ar atoms
→ Ar -
non -
single
-
molecular (not Art -
limited HW's
-
diff sizes of molecules -
low BPTIMPT
Ar monatomic weak Vdw 's least amount of
energy explanation
-
-
:
-
Az stronger weak Vdw 's I Ar the electrons
-
lmore more than more
energy
e
-
-
-
,
Py e- stronger KW 's than Ar , 11 the stronger the Van
more more
energy
- -
-
-
( Tir: I
-
der Wall forces
G bigger molecules more e =
stronger Vdw 's most
energy
-
-
,
i.
higher MPTIBPT
electronegativity
trend :
across period inweasesm explanation :
more
pt in nucleus
smaller AR
change shielding
-
more e i no in
electrical
conductivity
trend : Na ,
Mg ,
Al -
good conductors explanation :
conductivity increases Na AL Na Al -
→
-
Si -
semiconductor
.
metals
conductors of the de localised electrons
None of the rest conduct
electricity
'
cos
rest
-
simple molecular
free electrons
no
moving
•
