what type of bond do aluminum and chlorine form? alcl 3

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Aluminum Chloride WHAT TYPE OF BOND DO ALUMINUM AND CHLORINE FORM? AlC l 3

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Page 1: WHAT TYPE OF BOND DO ALUMINUM AND CHLORINE FORM? AlCl 3

Aluminum Chloride

WHAT TYPE OF BOND DO ALUMINUM AND CHLORINE FORM?AlCl3

Page 2: WHAT TYPE OF BOND DO ALUMINUM AND CHLORINE FORM? AlCl 3

Aluminum Chloride

WHAT TYPE Of BOND DO ALUMINUM AND CHLORINE FORM?

Ionic: Metal and NonMetal

AlCl3

Page 3: WHAT TYPE OF BOND DO ALUMINUM AND CHLORINE FORM? AlCl 3

Aluminum Chloride

WHAT TYPE Of BOND DO ALUMINUM AND CHLORINE FORM?

Ionic: Metal and NonMetal

COVALENT BOND

AlCl3

Page 4: WHAT TYPE OF BOND DO ALUMINUM AND CHLORINE FORM? AlCl 3

Confused?

To muddy waters even further, there is no such thing as a purely ionic or covalent bond.AlCl3

Page 5: WHAT TYPE OF BOND DO ALUMINUM AND CHLORINE FORM? AlCl 3

Electronegativity

--

-- -

-

-

-

-

- -+11A measure of an atom or group of atom’s tendency to attract electrons

Page 6: WHAT TYPE OF BOND DO ALUMINUM AND CHLORINE FORM? AlCl 3

As you go across a period Electronegativity increases.

As you go down a group Electronegativity

decreases.

Additional Electron shielding and increased distance from the nucleus makes adding a new electron more difficult

Increasing nuclear charge (pull) without any additional shielding makes makes adding an electron easier.

Page 7: WHAT TYPE OF BOND DO ALUMINUM AND CHLORINE FORM? AlCl 3

Electronegativity (χ) is a “rule of thumb”Bond type is to Δ∝ χ

Page 8: WHAT TYPE OF BOND DO ALUMINUM AND CHLORINE FORM? AlCl 3

Δ Electronegativity

ELECTRON TUG OF WAR!

Page 9: WHAT TYPE OF BOND DO ALUMINUM AND CHLORINE FORM? AlCl 3

Electron Tug of WarH-H Hydrogen 2.20H-F Fluorine 3.98

Page 10: WHAT TYPE OF BOND DO ALUMINUM AND CHLORINE FORM? AlCl 3

Electronegativity Sliding Bond Scale

Δχ Bond Type Example

0.0-0.5 Non-Polar Covalent H2

≥0.5 to >1 Polar Covalent HCl

≥1 to <2 Very Polar Covalent HF

≥2 Ionic Bond Na+Cl-

Electron Tug of War

NaClH2OCO2

Page 11: WHAT TYPE OF BOND DO ALUMINUM AND CHLORINE FORM? AlCl 3

Water is a Polar Molecule!

Drops on a PennySnapping DropsSurface Tension

Sand vs SnowmanCapillary ActionMelting PointsBoiling Points

Solubility

H2O

Oxygen 3.44Hydrogen 2.20

Page 12: WHAT TYPE OF BOND DO ALUMINUM AND CHLORINE FORM? AlCl 3

Carbon Dioxide is Non-Polar

Why is Carbon dioxide non-polar?

CO2

Oxygen 3.44Carbon 2.55Δχ=0.89OO C

Page 13: WHAT TYPE OF BOND DO ALUMINUM AND CHLORINE FORM? AlCl 3

Carbon Dioxide is Non-Polar

Why is Carbon dioxide non-polar?

CO2

Oxygen 3.44Carbon 2.55Δχ=0.89OO C

δ+δ- δ-

Because it is linear or perfectly symmetrical.

Page 14: WHAT TYPE OF BOND DO ALUMINUM AND CHLORINE FORM? AlCl 3

Carbon Dioxide is Non-Polar

Why is Carbon dioxide non-polar?

CO2

Oxygen 3.44Carbon 2.55Δχ=0.89OO C

δ+δ- δ-

Because it is linear or perfectly symmetrical.

Page 15: WHAT TYPE OF BOND DO ALUMINUM AND CHLORINE FORM? AlCl 3

O

Water is Bent

Why is Water Polar?HHδ+δ+

δ-

Because water is not a linear molecule.

Page 16: WHAT TYPE OF BOND DO ALUMINUM AND CHLORINE FORM? AlCl 3

O

MOLECULAR GEOMETRY: VSEPR

Why is Water Polar?HH

δ-

δ+ δ+

Because water is not a linear molecule.

Page 17: WHAT TYPE OF BOND DO ALUMINUM AND CHLORINE FORM? AlCl 3

What about HCN?

Prussic Acid is Polar

CO2

Hydrogen 2.20Carbon 2.55NitrogenNH C

δ+ δ-

Because it is linear but the ends have opposite charges.

Page 18: WHAT TYPE OF BOND DO ALUMINUM AND CHLORINE FORM? AlCl 3

Two types of Covalent Bonds

Non-Polar Covalent• Electrons Shared Equally:• --all diatomic molecules

Polar-Covalent• Electrons Shared Unequally• --due to electronegativity

δ Small Delta indicates PARTIAL CHARGES

There is a small degree of sharing and orbital overlap even in ionic bonds.

Page 19: WHAT TYPE OF BOND DO ALUMINUM AND CHLORINE FORM? AlCl 3

Practice ProblemsWhat type of bond will form between the following atoms?

a) N and Hb) F and F

c) Ca and Cld) Al and Cle) H and Brf) K and Clg) C and Oh) Cl and Fi) Li and Oj) H and O

Δ Electronegativity Bond Type0.0-0.5 Non-Polar Covalent

≥0.5 to >1 Polar Covalent≥1 to <2 Very Polar Covalent

≥2 Ionic Bond (Extremely Polar)

Page 20: WHAT TYPE OF BOND DO ALUMINUM AND CHLORINE FORM? AlCl 3

Practice ProblemsWhat type of bond will form between the following atoms? a) N (3) and H (2.1) = 0.9 mod PCb) F (4) and F(4) = 0 = non-polar

c) Ca (1) and Cl (3) = 2 = Ionicd) Al (1.5) and Cl (3) = 1.5 = very PCe) H and Br mod PCf) K and Cl ionic g) C and O mod to very PCh) Cl and F mod to very PCi) Li and O ionicj) H and O polar (thisH20!)

Place these covalent bonds in order of least to most polar.

• H—CL• H—Br• H—S• H—C

Answer: C and D tie to B to A