Chapter 18: Basic Concepts of Chemical Bonding

Question 1

Where are valence electrons found on the atom?

Answer 1

Outermost shell

Question 2

Define “lattice energy (LE)”

Answer 2

The energy of formation of the crystal from infinitely-separated ions, molecules, or atoms, and as such is invariably negative

Question 3

Lattice energy _________ with the charges on the ions

Answer 3

Increases

Question 4

LE also increases with __________ size of ions

Answer 4

Decreasing

Question 5

Identify all the characters in the following equations:

Eel=(kQ1Q2)/d

Answer 5

Eel = Lattice energy
k = 8.99x10^(9) J*M/c^2
d = distance between the two centers
Q1 and 2: charges on the particles

Question 6

LE is generally large enough to compensate for the loss of up to _ electrons from atoms

Answer 6

3

Question 7

In forming ions, transition metals lose the _______-shell _ electrons first, then as many _ electrons as required to reach the charge of the ion

Answer 7

valence, s, d

Question 8

Define a covalent bond

Answer 8

A pair of electrons shared between two usually nonmetal atoms.

Question 9

Define electronegativity

Answer 9

The measure of attraction an atom has for shared electrons.

Question 10

Electronegativity _________ from left to right across a row and from bottom-up.

Answer 10

Increases

Question 11

The greater the difference in electronegativity, the more _____ the bond is.

Answer 11

polar

Question 12

Define dipole moments

Answer 12

When two atoms share electrons unequally.

Question 13

Identify the characters in the following equation:

μ=Qr

Answer 13

μ = dipole moment in debyes (D)
Q = charges on the particle
r = radius in angstroms (Å)