Unit 4 Bonding

What are intramolecular forces?

Forces within a molecule (ionic, covalent, metallic).

What are intermolecular forces?

Forces between molecules.

What phrase do you use for phase change?

Overcoming intermolecular forces.

What is the octet rule?

Atoms want a full valence shell like noble gases.

What does electronegativity measure?

How strongly an atom attracts electrons.

What happens to energy when a bond forms?

Energy is released.

What happens to energy when a bond breaks?

Energy is absorbed.

What forms an ionic bond?

Metal + nonmetal; electron transfer.

Are ionic bonds polar?

Yes — always.

What forms a covalent bond?

Nonmetal + nonmetal; electron sharing.

Are covalent bonds polar or nonpolar?

Can be either.

Single bond length/strength?

Longest / weakest.

Triple bond length/strength?

Shortest / strongest.

More electrons shared = ?

Shorter, stronger bond.

What is a polyatomic ion?

Covalently bonded group with a net charge.

Can polyatomic ions bond with metals?

Yes — forming ionic + covalent bonds in the same substance.

Define metallic bonding.

Positive ions in a sea of mobile electrons.

Why are metals conductive?

Mobile valence electrons.

Why are metals malleable/ductile?

Metallic bonding allows layers to slide.

What is polarity?

Unequal sharing of electrons causing partial charges.

What is a nonpolar bond?

Equal sharing; same or similar nonmetals.

What is a polar bond?

Unequal sharing; different nonmetals.

END for nonpolar bonds?

0–0.4

END for polar covalent bonds?

0.5–1.7

END formula?

Higher EN − Lower EN