polar and non-polar + electronegativity

s

Are electrons shared equally or unequally in POLAR bonds?

Unequally

Are electrons shared equally or unequally in NON-POLAR bonds?

Equally

What is the distribution of electrons defined by? (hint: it has to do with electronegativity)

The difference in electronegativity

What is electronegativity?

The tendency of an atom to gain an electron

What is polarity?

Uneven distribution of electrical charge in a molecule = partially positive & partially negative ends

What makes a molecule POLAR?

An uneven distribution of charge, has a partially positive and partially negative end

What makes a molecule NON-POLAR?

Charge is distributed evenly, does not have partially positive or negative ends

What makes a bond POLAR?

Electrons are shared UNEQUALLY between atoms

What makes a bond NON-POLAR?

Electrons are shared EQUALLY between atoms

What is a dipole?

A separation of positive and negative charge WITHIN a bond or molecule

TRUE OR FALSE: A molecule can have polar bonds but still be non-polar

TRUE

Why can molecules with polar bonds still be non-polar overall? (hint: c)

The bond polarities cancel out

Why do bond polarities cancel each other out in overall non-polar molecules? (HINT: think of CO2)

The atoms pull electrons with equal strength, however it is opposite to one another.

Why do bond polarities don’t cancel each other out in overall polar molecules? (hint: think of H2O)

The direction of pulling electrons are not opposite to one another,

Fill in the blanks:

Polar bonds + ______ = can cancel —> _____

symmetrical arrangement, non-polar molecule

Fill in the blanks:

Polar bonds + _______ = _______ —> polar molecule

asymmetrical arrangement, don’t cancel

Are linear shapes symmetrical or asymmetrical? (hint: think of CO2)

Symmetrical

Are bent shapes symmetrical or asymmetrical?

Asymmetrical

What is the flow of determining the molecule being overall POLAR from the shape? And if its bonds cancel each other out?

Asymmetrical shape —> polarities usually don’t cancel —> polar molecule

What is the flow of determining the molecule being overall NON-POLAR from the shape? And if its bonds cancel each other out?

Symmetrical shape —> polarities can cancel —> non-polar molecule

What does it mean when the electronegativity difference between different molecules are larger? (hint: it has to do with the type of bonds)

Larger electronegativity difference = ionic bond

If the electronegativity difference is <0.5, what bond would it be? And would it be polar or non-polar?

<0.5 = nonpolar covalent bond

If the electronegativity difference is 0.5 - 1.7, what bond would it be? And would it be polar or non-polar?

0.5 - 1.7 = polar covalent bond

If the electronegativity difference is >2.0, what bond would it be? (hint: polarity doesn’t matter at this point)

>2.0 = ionic bond