Intro Chemical Bonding Part 2

Review Questions

Multiple Choice

Why do all bonds form?

• To fill up the outer shell and become more stable.

• To look cool.

• To become less stable.

• So they don't have to be alone.

Multiple Choice

If Nitrogen bonded with Oxygen, would it form a covalent bond or an ionic bond?

• covalent

• ionic

Multiple Choice

When an atom completely gives up its valence electrons to another atom, they form a bond that is considered to be

• purely ionic.

• polar-covalent.

• nonpolar-covalent.

Multiple Choice

You can estimate the degree to which a bond between two atoms is

• distance between the atoms' nuclei.

• difference in the atoms' electronegativities.

• atoms' atomic radii.

• number of atoms in the compound.

3.0 - 3.0 = 0.0
Nonpolar

3.0 - 2.1 = 0.9
Polar

3.0 - 0.9 = 2.1
Ionic

Examples:

• Cl2

• HCl

• NaCl

Polar Covalent: an uneven sharing of
electron—resulting in an asymmetrical electron
density.

Non-Polar Covalent: an even sharing of
electron—resulting in an symmetrical electron density.

Ionic Bonding: a complete transfer of
electron—resulting in oppositely charged ions.

e-

Cl

Use electronegativity values to classify
bonding between:

Oxygen (O) and Oxygen (O)
Cesium (Cs) and Fluorine (F)
Chlorine (Cl) and Phosphorus (P)

Practice

Multiple Choice

Oxygen and Oxygen

• Nonpolar Covalent Bond

• Polar Covalent Bond

• Ionic

Multiple Choice

Cesium and Fluorine

• Nonpolar Covalent Bond

• Polar Covalent Bond

• Ionic

Multiple Choice

Chlorine and Phosphate

• Nonpolar Covalent Bond

• Polar Covalent Bond

• Ionic

Bonding END

Bond type More negative atom

Cs and F

4.0 – 0.8 = 3.2

ionic

fluorine

Cl and P

3.0 – 2.2 = 0.9

polar-covalent

chlorine

O and O

3.5 – 3.5 = 0.0

nonpolar-covalent

NA

Practice Solution

Wrapping it Up!

Nonpolar Covalent Bond

✔ electrons are shared equally

✔ symmetrical electron density

✔ usually identical atoms

Polar Covalent Bond

✔ electrons are shared unequally

✔ asymmetrical electron density

✔ results in partial charges

Wrapping it Up!

Wrapping it Up!

Ionic Bond

✔ electrons are transferred

✔ ions are formed

✔ electrostatic attraction between

cations and anions

Ionic Bond

Ionic Bond

Ionic – transfer of electrons

(Metal + Non-metal)

Did you notice this?

Covalent – sharing of electrons

(Non-metal + Non-metal) (Non-metals + Metalloids

Did you notice this?

Non-polar

Polar