Molecular polarity

Question 1

What makes a structure asymmetricla

Answer 1

Center is exposed OR there are atoms of different electonegativies bonding around the central atom

Question 2

What types of intermolecular forces are there between neutral molecules

Answer 2

• London Dispersion (LDF)
• Dipole-Dipole forces (DD)
• Hydrogen bonding

Question 3

How many electrons does boron take

Answer 3

6

Question 4

# of atoms boded to central atom: 3
# of unshared electron pairs on central atom: 1

Answer 4

Trigonal pyramidal

Question 5

# of atoms boded to central atom: 2
# of unshared electron pairs on central atom: 0

Answer 5

Linear

Question 6

London dispersion forces (LDF)

Answer 6

• Atrraction caused by a temporary, uneqeual distribution of electrons, which cause a momentary positive/negative area on a molecule
• Made stronger by more electrons in the molecule
• Found in all atoms and molecules ( even noble gases)

Question 7

What makes molecules stick together

Answer 7

Forces that exist between molecules called intermolecular forces

Question 8

# of atoms boded to central atom: 1
# of unshared electron pairs on central atom: 1

Answer 8

Linear

Question 9

# of atoms boded to central atom: 1
# of unshared electron pairs on central atom: 2

Answer 9

Linear

Question 10

What makes a molecule polar

Answer 10

1. It has polar bonds

2. It is asymmetrical (center is exposed or atoms of dif electronegativities bonded to center)

Question 11

How do you mix substances

Answer 11

You need two substances with the same type/strength of IMF
EX: Only things with LDF dissolve/mix in things with only only LDF
-DD forces interact well with other DD forces (Hyrdogen bonding is a stong DD force)

Question 12

What makes the central exposed

Answer 12

It has unshared electrons

Question 13

How to tell difference in strength for DD

Answer 13

-HB the strongest. Otherwise whichever has greater electronegativity difference

Question 14

# of atoms boded to central atom: 3
# of unshared electron pairs on central atom: 0

Answer 14

Trigonal planar

Question 15

Exeptions to the 8 electron rule

Answer 15

B only takes 6 valence electrons

H only take 2 valence electrons (1 Bond)

Question 16

# of atoms boded to central atom: 4
# of unshared electron pairs on central atom: 0

Answer 16

Tetraheda

Question 17

Dipole-Dipole forces (DD)

Answer 17

• Attraction caused by permanently establish dipoles on molecules (the partial positive and partial negative charge)
• Found in polar molecules
• Stronger with a greater electronegativity difference

Question 18

Hydrogen bonding

Answer 18

-Extremely stong dipole
-Found when hydrogen is bonded to N, O, or F directly
and it has unshared electrons

Question 19

# of atoms boded to central atom: 2
# of unshared electron pairs on central atom: 2

Answer 19

Bent

Question 20

What does strong IMF mean

Answer 20

• Higher boiling point
• Higher melting point
• Lower vapor pressure (less evaporation)

Question 21

How many electrons does Barrilium take

Answer 21

4

Question 22

# of atoms boded to central atom: 2
# of unshared electron pairs on central atom: 1

Answer 22

Bent

Question 23

The stronger the IMF….

Answer 23

The more the molecules want to stick together

Question 24

What is the substance mixing rule

Answer 24

-Like dissolves like

Polar dissolves polar, nonpolar dissolves nonpolar

Question 25

# of atoms boded to central atom: 1
# of unshared electron pairs on central atom: 3

Answer 25

Linear

Question 26

How to tell difference in strength for LDL things

Answer 26

-The one with more total electrons is stronger

Question 27

What makes bond polar

Answer 27

If electronegativity is different

Question 28

How many electrons does hydrogen take

Answer 28

2-> one line