Chapter 8

Question 1

Linear

Answer 1

2 bonding 0 non bonding

180°

Question 2

Triganol planar

Answer 2

3 non bonding 0 non bonding

120°

Question 3

Tetrahedral

Answer 3

4 bonding 0 non bonding

109.5°

Question 4

Triganol bypramidal

Answer 4

3 bonding 1 non bonding

107°

Question 5

Bent

Answer 5

2 bonding 0 non bonding

120° 90°

Question 6

Octahedral

Answer 6

6 bonding 0 non bonding

90°

Question 7

Hydrogen is NOT a _________

Answer 7

metal

Question 8

Helium is a _______

Answer 8

Noble has

Question 9

how many electrons does a covalent bond have ?

Answer 9

2 electrons

Question 10

Lewis structures

Answer 10

•1916
•electron dot structures show valence electrons 
•used for "A" groups only
[ ] - ion
No [ ] then no ion

Question 11

Lewis dot diagrams

Answer 11

•used only for molecules
•when drawing them
1.sum of of valence electrons
2. Write symbols/atoms in order
3. Complete octets of atoms bonded to central atoms
4. When you don’t have enough electrons, to give to an central, an octet tries multiple bonds

Question 12

VSEPR theory

Answer 12

• Valence Shell Electron Pair Repulsion
• molecules adjust shape to decrease electron repulsion
• geometry determined by counting domains
1. Bonding pair
2. Nonbonding

Question 13

Bond length & strength

Answer 13

•distance between atoms decreases as number of shared electrons increases
N-N N=N N(3 bonds)N
1.47 A. 1.24 A. 1.10 A

Question 14

Triple bonds

Answer 14

• smallest,more stable, shortest
• Very stable
• Earths atmosphere is 78% N2 due to its stability

Question 15

Nitrogen fixation occurs in_______________

Answer 15

Bacteria in the root modules of legumes (beans)

Question 16

Intermolecular forces:

Answer 16

Ion-dipole forces
•interaction between an ion and a dipole
• opposites attract
• water has the ability to go and get ions (only if soluable)
• salt dissolved in water
• STRONGEST OF ALL

Question 17

Vanderwalls forces

Answer 17

• dipole-dipole forces
• polar molecules
• intermediate strengths (not strong, not weak)
• most polar, bigger attraction
• exists in liquids

Question 18

London dispersion forces (LDF)

Answer 18

• constant random motion of electrons about atom creates temporary positive and negative charges.
• Very weak (weakest) –> because poles are temporary
•Instintanious dipole induces dipole
-liquid N2 -196° C (77K)
• all molecules exhibit dispersion forces
•strengths increase w/ atomic size
-large electron clouds are polarizable
• trends in halogens