Lecture 15

Question 1

Ionic bonding

Answer 1

• Electron transfer
• metal + nonmetal
• Na+ Cl-

Question 2

Covalent bonding

Answer 2

• electron sharing
• non-metal - + non-metal
• C—C, C—O

Question 3

Metallic bonding

Answer 3

• election pooling
• metal + metal
• Na Na

Question 4

Lattice energy

Answer 4

• depends on charge and radius
• Energy required to separate one mole of an ionic solid into gaseous ions (or the energy released when a mole of ionic solid is formed from gaseous ion)
• cannot be measured directly, but can be estimated using the Born-Haber cycle

Question 5

What is the cause of lattice energy?

Answer 5

Electrostatic interactions of ions

Question 6

Coulomb’s law definition

Answer 6

Electrostatic energy of attraction or repulsion between two charges (Q1 and Q2) is direction proportional to the produce of their magnitudes

Question 7

Coulomb’s law equation

Answer 7

E ∝ (Q1*Q2) / r

r: distance between cations and anions is the sum of the individual radii)

Question 8

What happens to lattice energy when the ionic charge increases?

Answer 8

Lattice energy becomes more exothermic

Question 9

If ionic charge increases….then

Answer 9

• Electrostatic interaction increases
• Lattice energy increases

Question 10

Considering lattice energy, if you double the charges…then

Answer 10

The energy quadruples

Question 11

Ionic compounds

Answer 11

Transferring lecterns creates closed shells

Question 12

Covalent compounds

Answer 12

Sharing electrons creates closed shells in most covalent compounds