Chemistry Test: Bonding

2,0

Linear

3,0

Trigonal planar

2,1

Bent

4,0

Tetrahedral

3,1

Trigonal pyramidal

2,2

Bent

5,0

Trigonal bipyramidal

4,1

Seesaw

3,2

T-shaped

2,3

Linear

6,0

Octahedral

5,1

Square pyramidal

4,2

Square planar

2: Linear

180 degrees

3: Trigonal Planar

120 degrees

4: Tetrahedral

109.5 degrees

5: Trigonal Bipyramidal

120 and 90 degrees

6: Octahedral

90 degrees

Hydrogen rule

It wants two, not eight

Octet rule

It wants eight

London Dispersion

All molecules have this by default. Fleeting, unlike the other 2 IMF’s.

Dipole-dipole

Polar bonds have this. High melting/boiling points.

Hydrogen bond

If there is a combination of N-H, O-H or F-H. Nice Old Folks hate fun! This causes water's special properties.

Nonpolar bond from Lewis

If central atom has no lone pairs, AND all atoms around central atom are the same. Otherwise, it’s polar.

Hierarchy of bonds

A hydrogen bond also has the two forces that come before it (DP-DP and LD).

Stronger intermolecular forces

Count how many: LD, DP-DP, HB. If there’s a tie, it’s whichever has the higher weight.

Ionic Bonds

Transfer of electrons with a cation and anion. Usually metal x nonmetal; dissolve in water to form ions; conducts electricity when dissolved; high melting and boiling points; electronegative difference greater than 1.67.

My Night Wolves Call Home: Metal, nonmetal, dissolves, conducts, high points.

Covalent

Sharing of electrons (COoperation). Can be polar or nonpolar. Usually between nonmetal x nonmetal; do not dissolve to make ions; don’t conduct electricity.

2 New Neighbors Dance: 2 Nonmetals, no ions formed, don’t conduct.

Cation

Positive ion

Anion

Negative ion

Nonpolar bonds

Even sharing; electronegative difference less than 0.4.

Polar bonds

Uneven sharing; electronegative difference between 0.4 and 1.67.

Metallic bonds

They’re with metals. They’ve got delocalized electrons (big words for free to move around). That also allows for conductivity in solid/molten state.

Hybridization

Add the number of bonded atoms and number of unbonded electron pairs. Take that number of letters from “spppddddd.”

VSEPR

Valence Shell Electron Pair Repulsion. Predicts shapes.

Sigma bond

All single bonds and one of the bonds in a multiple.

Pi bonds

The remaining bonds in a multiple that aren’t sigma.

Asymmetric shapes

Bent, trigonal, pyramidal, see-saw, T-shaped, square pyramid. Big Tall People Serve Tasty Snacks.

Charges in Lewis

Do the opposite of the charge to your total count and use brackets. For example, if it says +2, subtract 2 from your count. Put your model in brackets with the “+2” charge at the top right.

Partial Charges

If polar, the atom closest to the top right gets a partial negative (𝛿−) and the one closest to the bottom left gets a partial positive (𝛿+). If there’s three, one doesn’t get a partial charge.

Lewis Exceptions

Whenever you have too many electrons- distribute evenly and then give the rest to the central atom.