AP Chem Bonding

+ Enthalpy of Formation

endothermic

- Enthalpy of Formation

exothermic

+ Lattice Energy

bonds being broken (endothermic)

- Lattice Energy

compound forming (exothermic)

smaller particle separation (smaller ionic radii)

higher lattice energy

larger particle separation (larger ionic radii)

lower lattice energy

w/ transition metal ions, electron(s) lost is from

subshell w/ highest n value

large difference in EN

ionic

small diff. in EN, both higher

covalent

small diff. in EN, both low

metallic

In an isoelectronic series, relative size depends on

# of protons

nonpolar covalent

equal sharing of electrons

polar covalent

unequal sharing of electrons

electronegativity (EN)

the ability of an atom in a molecule to attract electrons to itself

bonded atom w/ large EN

great ability to attract electrons

bonded atom w/ small EN

doesn't attract electrons well

Difference in EN < .5

nonpolar covalent bond

0.5 ≤ Difference in EN < 2.0

polar covalent bond

Difference in EN ≥ 2.0

ionic bond

Polar covalent molecules have partial charges and thus have a

Dipole Moment

Large Difference in EN = high polarity =

major dipole moment

Polar molecules tend to align themselves w/

eachother and ions

compounds of metals with higher oxidation #'s

tend to be molecular