Polar, Non-Polar & Hydrogen Bonds

Packet #20

Types of Chemical Bonds

Polar Bond

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Remember…

Bond Polarity is due to differences in electro-negativity

Bond polarity can predict the polarity of a bond

∆EN < 0.4 = non-polar covalent

∆EN between 0.4 and 2.0 = polar covalent

∆EN > 2.0 = ionic

δ used to indicate partial charges

Dipole movement is the measure of a molecule’s overall polarity

μ = Q (charge) * r (distance)

More details to come in Organic Chemistry

Bond Polarity & Chemical Bonds

Polar Bond

A polar bond is formed because one atom, of the compound, being more electronegative grabs more electron density from another atom.

The electronegative atom attempts to steal electrons.

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Types of Chemical Bonds

Non-Polar Bonds

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Non-Polar Bond

Joining of atoms with the same electronegativity

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Types of Chemical Bonds

Hydrogen Bonds

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Hydrogen Bonds

A strong non-bonding interaction that causes a quick, weak “chemical bond.”

Occurs when a hydrogen atom, attached to a highly electronegative atom, interacts with a lone electron from a nearby electronegative atom.

These bonds are broken almost immediately

Depends on temperature.

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Hydrogen Bond

Although hydrogen bonds are weak, the vast number of them in large molecules makes them collectively significant

The formation of water in various forms.

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Phases of Matter

Liquid

Solid

Gas

Elements and molecules can exist in all three phases

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Phases of Matter II

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Van der Waals Forces

Review