Chapter 3: Molecules, Ions And Ionic Compounds

Question 1

Molecules are made up of two or more atoms joined by ______ bonds

Answer 1

Covalent

Question 2

A _____ bond forms when two atoms share valence electrons between them.

Answer 2

Covalent

Question 3

How are binary inorganic molecules named?

(Molecules made of two covalently bound non-metals)

Answer 3

-Contains Hydrogen:
No prefix then follow rules 1-3.

-No Hydrogen:

1. Use prefixes for number of atoms (mono, do, tri, tetra, etc.) Note: “Mono-“ not used for first element.
2. Second element ends with “-ide”.
   Note: this is also explicitly mentioned in the rules of fixed-charge nonmetal anions.
3. If prefix ends with “a” or “o”, drop the final vowel.

Question 4

• 2 electron groups
• 2 bonding groups
• 0 lone pairs
• 180°

Electron Group Geometry: ?
Molecular Shape: ?

Answer 4

Electron Group Geometry: linear
Molecular Shape: linear

Question 5

• 3 electron groups
• 3 bonding groups
• 0 lone pairs
• 120°

Electron Group Geometry: ?
Molecular Shape: ?

Answer 5

Electron Group Geometry: Trigonal planar
Molecular Shape: Trigonal planar

Question 6

• 3 electron groups
• 2 bonding groups
• 1 lone pairs
• 120°

Electron Group Geometry: ?
Molecular Shape: ?

Answer 6

Electron Group Geometry: Trigonal planar
Molecular Shape: Bent

Question 7

• 4 electron groups
• 4 bonding groups
• 0 lone pairs
• 109.5°

Electron Group Geometry: ?
Molecular Shape: ?

Answer 7

Electron Group Geometry: Tetrahedral
Molecular Shape: Tetrahedral

Question 8

• 4 electron groups
• 3 bonding groups
• 1 lone pairs
• 109.5°

Electron Group Geometry: ?
Molecular Shape: ?

Answer 8

Electron Group Geometry: Tetrahedral
Molecular Shape: Trigonal PYRAMIDAL

Question 9

• 4 electron groups
• 2 bonding groups
• 2 lone pairs
• 109.5°

Electron Group Geometry: ?
Molecular Shape: ?

Answer 9

Electron Group Geometry: Tetrahedral
Molecular Shape: Bent

Question 10

Fixed charge metals rules:

Answer 10

• Group 1A (¹⁺ cations — lose one electron)
• Group 2A (²⁺ cations — lose two electrons)
• Al³⁺
• Zn²⁺
• Cd²⁺
• Ag⁺

Question 11

Fixed charge non-metals rules:

Answer 11

• Group 5A (^3- that gain 3 electrons)
• Group 6A (^2- that gain 2 electrons)
• Group 7A (^1- that gain 1 electron)

Note: Anions end in “-ide”.
COVALENT BONDS — remember the rules for naming Binary Inorganic Compounds.

Question 12

Naming Polyatomic Cations:
(Without oxygens)

Answer 12

The names end in ”-ium”

Ex. NH₄⁺ (Ammonium)

Question 13

Naming Polyatomic Anions:
(Containing hydrogens and oxygens)

Answer 13

Names end in ”-ate” or ”-ite”.

• The formula with less oxygens uses ”-ite”.
• The formula with more oxygens uses ”-ate”.

Note: Many polyatomic anions contain oxygen and are called oxoanions.

• NO₂^- (Nitrite)
• NO₃^- (Nitrate)

If an oxoanion has more than two members:
- “hypo-“
- ”-ite”
- ”-ate”
- ”per-“

Additional hydrogens in oxoanions are named by adding the prefixes ”di-“, ”tri-“, etc.

• HPO₄^2- : hydrogen phosphate
• H₂PO₄^- : dihydrogen phosphate

Note: Polyatomic anions without oxygen end in ”-ide”.

Question 14

Ionic Compound Nomenclature:

Answer 14

• Prefixes not used.
• Use cation name as the first name and anion name as the second name.