electro- negativity. ionic covalent continuum when chlorine and hydrogen react the covalently bonded...
TRANSCRIPT
Electro-negativity
Ionic covalent continuum When chlorine and hydrogen react the
covalently bonded HCL is made
When chlorine and sodium react ionicly bonded NaCl is formed
Why does Cl share electrons with H yet remove electrons from Na?
Why does Cl share electrons with H yet remove electrons from Na?
Hydrogen holds its electrons really tightly in H-H gas
Sodium is a metal the doesn’t hold it’s valance electrons as tightly
Chemists use the term electronegativity
ElectronegativityElectronegativityWhat is it?
• Electronegativity is the power of an atom to attract electron density
Remember the above definition …
in a covalent bond
Or in layman's terms the “attractiveness” of an atom to
electrons in a bond
ElectronegativityElectronegativityPauling’s electronegativity scale
• The higher the value, the more electronegative the element
• Fluorine is the most electronegative element
• It has an electronegativity value of 4.0
ElectronegativityElectronegativityPauling’s electronegativity scale
ElectronegativityElectronegativityPauling’s electronegativity scale
F
ElectronegativityElectronegativityPauling’s electronegativity scale
F4.0
ElectronegativityElectronegativityPauling’s electronegativity scale
Li1.0
F4.0
ElectronegativityElectronegativityPauling’s electronegativity scale
Li1.0
Be1.5
F4.0
ElectronegativityElectronegativityPauling’s electronegativity scale
Li1.0
Be1.5
B2.0
F4.0
ElectronegativityElectronegativityPauling’s electronegativity scale
Li1.0
Be1.5
B2.0
C2.5
F4.0
ElectronegativityElectronegativityPauling’s electronegativity scale
Li1.0
Be1.5
B2.0
C2.5
N3.0
F4.0
ElectronegativityElectronegativityPauling’s electronegativity scale
Li1.0
Be1.5
B2.0
C2.5
N3.0
O3.5
F4.0
ElectronegativityElectronegativityPauling’s electronegativity scale
Li1.0
Be1.5
B2.0
C2.5
N3.0
O3.5
F4.0
Na0.9
Mg1.2
Al1.5
Si1.8
P2.1
S2.5
Cl3.0
ElectronegativityElectronegativityPauling’s electronegativity scale
H He
Li1.0
Be1.5
B2.0
C2.5
N3.0
O3.5
F4.0
Ne
Na0.9
Mg1.2
Al1.5
Si1.8
P2.1
S2.5
Cl3.0
Ar
ElectronegativityElectronegativityPauling’s electronegativity scale
H2.1
He
Li1.0
Be1.5
B2.0
C2.5
N3.0
O3.5
F4.0
Ne
Na0.9
Mg1.2
Al1.5
Si1.8
P2.1
S2.5
Cl3.0
Ar
ElectronegativityElectronegativityPauling’s electronegativity scale
H2.1
He-
Li1.0
Be1.5
B2.0
C2.5
N3.0
O3.5
F4.0
Ne-
Na0.9
Mg1.2
Al1.5
Si1.8
P2.1
S2.5
Cl3.0
Ar-
So what does all this mean? Same atoms bonding
= same electronegativity = pure covalent bond
Different atoms bonding=different electronegativity
= Polar covalent or Ionic bondConfused? How do we tell which one?
Difference in electronegativity Covalent and ionic are a opposite ends of the same scale
Covalent
Ionic Bond
Polar Covalent
If the difference in electronegativities is between:
1.7 to 4.0 = Ionic Bond
0.3 to 1.7 = Polar Covalent
0.0 to 0.3 = Non-Polar Covalent