U4 Part 2 Test

Question 1

How do bonding pairs and lone pairs on the central atom affect the shape?

Answer 1

Bonding pairs are shared by 2 atoms, meaning they are spread out more creating less repulsion between them. With lone pairs, they are only held by a single atom and the electrons are more confined, causing more repulsion.

When the central atom has lone pairs the shape is trigonal pyramidal.
When the central atom has bonding pairs the shape is tetrahedral.

Question 2

What is VSEPR Theory?

Answer 2

Electrons that are in bonds or as lone pairs will always repel each other, thus the shape of the molecule can be predicted by assuming all electron domains bonding or non-bonding are spreading out as far from each other as possible.

Question 3

Linear angle

Answer 3

180°

Question 4

Bent angle

Answer 4

105°

Question 5

Trigonal planar angle

Answer 5

120°

Question 6

Trigonal pyramidal angle

Answer 6

107°

Question 7

Tetrahedral angle

Answer 7

109.5°

Question 8

Trigonal bi-pyramidal angle

Answer 8

120° and 90°

Question 9

Octahedral angle

Answer 9

90°

Question 10

What shape has 1 lone pair on the central atom and 3 bond pairs?

Answer 10

trigonal pyramidal

Question 11

What shape has 2 lone pairs on the central atom and 2 bond pairs?

Answer 11

bent

Question 12

What shape has 0 lone pairs on the central atom and 2 bond pairs?

Answer 12

linear

Question 13

What shape has 0 lone pairs on the central atom and 3 bond pairs?

Answer 13

trigonal planar

Question 14

What shape has 0 lone pairs on the central atom and 4 bond pairs?

Answer 14

tetrahedral

Question 15

Trigonal bi-pyramidal has __ bonding pairs and __ lone pairs on the central atom

Answer 15

5,0

Question 16

Octahedral has __ bonding pairs and __ lone pairs on the central atom

Answer 16

6,0

Question 17

is octahedral a non-polar or polar shape?

Answer 17

NP if all elements are the same around central atom

Question 18

is trigonal bi-pyramidal non-polar or polar shape?

Answer 18

NP if all elements are the same around the central atom

Question 19

is linear a non-polar or polar shape?

Answer 19

NP if all elements are the same around the central atom

Question 20

is trigonal planar a non-polar or polar shape?

Answer 20

NP if all elements are the same around the central atom

Question 21

is tetrahedral a non-polar or polar shape?

Answer 21

NP if all elements are the same around the central atom

Question 22

is bent a non-polar or polar shape?

Answer 22

P

Question 23

is trigonal pyramidal a non-polar or polar shape?

Answer 23

P

Question 24

List the IMFS from strongest to weakest

Answer 24

Ion-dipole, Hydrogen Bonding, Dipole-Dipole, London Dispersion

Question 25

Which IMF is found between all types of molecules (polar or nonpolar)

Answer 25

LD

Question 26

Which IMF is only found between polar molecules

Answer 26

di-di

Question 27

Hydrogen bonding is an attraction between a ____ atom attached to a highly _____ atom (F,O,N)

Answer 27

hydrogen, electronegative,

Question 28

Only Hydrogen bonding occurs when H is attracted to ___

Answer 28

F,O,N

Question 29

Which IMF occurs between an ion and a polar molecule?

Answer 29

ion-dipole

Question 30

In ion-dipole interactions, cations (+) are attracted to the ____ end of a dipole and anions (-) are attracted to the ____ end

Answer 30

negative, positive

Question 31

Importance of Hydrogen bonding in water

Answer 31

1. ice is less dense than liquid water
2. high surface tension, high melting and boiling points
3. lower vapor pressure
4. universal solvent