Unit 9 (chapter 12)

Question 1

bond

Answer 1

what holds atoms together

Question 2

bent

Answer 2

type of bond shape with 2 ligands and 2 lone pairs

Question 3

bond angle

Answer 3

angle between ligands

Question 4

bond energy

Answer 4

energy used to create or break a bond.
- during bond formation, energy is released, meaning it’s exothermic
- during bond breaking energy is absorbed, meaning it’s endothermic

Question 5

bonding pair

Answer 5

electrons that are shared between atoms in a bond (opposite of lone pair, which aren’t shared)

Question 6

covalent bond

Answer 6

• nonpolar
• molecules
• both nonmetals
• sharing electrons equally, between nuclei, overlap of orbitals
• electronegativity difference of 0, electronically symmetric
• usually 2 of the same atom

Question 7

dipole moment

Answer 7

aka property of polar molecule (synonyms)

Question 8

double bond

Answer 8

two bonds (4 electrons) shared between atoms

Question 9

electronegativity

Answer 9

the tendency of an atom participating in a covalent bond to attract the bonding electrons

Question 10

geometry

Answer 10

the three-dimensional arrangement of the atoms and chemical bonds in a molecule

Question 11

isomers

Answer 11

One of two or more compounds that have the same chemical formula but different arrangements of the atoms within the molecules

Question 12

ionic bond

Answer 12

• transfer of electron(s)
• between metal and nonmetal. metal becomes cation and goes down in energy, nonmetal becomes anion and goes up in energy
• must be close together, touching
• electronegativity difference of >1.7

Question 13

lewis dot structure

Answer 13

for molecules

Question 14

lewis dot symbol

Answer 14

for single atoms

Question 15

linear

Answer 15

2 ligands, 0 lone pairs

Question 16

lone pair

Answer 16

pair of electrons on molecule that is only connected to central atom

Question 17

nonpolar molecule

Answer 17

molecules comprised with atoms that have the same electronegativity

Question 18

polar covalent bond

Answer 18

• between two nonmetals
• electronegativity difference 0<x<1.7
• partial charges
• different atoms

Question 19

polar molecule

Answer 19

molecule with atoms of different electronegativities. covalent

Question 20

octet rule

Answer 20

atoms will gain/lose/share electrons to get to 8 (except B that wants 6)

Question 21

resonance

Answer 21

• a condition when more than one lewis structure can be/has to be drawn for a particular molecule or polyatomic
• atoms do not move; e- pairs changes from long to bonding pairs
• the actual electronic structure does not actually match any one individual lewis structure, but rather is the average of all of them

Question 22

resonance structure

Answer 22

• a condition when more than one lewis structure can be/has to be drawn for a particular molecule or polyatomic ion
• atoms do not move; e- pairs change form lone to bonding pairs
• the actual electronic structure does not match any one individual lewis structure, but rather is the average of them all

Question 23

tetrahedral

Answer 23

4 ligands, 0 lone pairs

Question 24

trigonal planar

Answer 24

3 ligands, 0 lone pairs

Question 25

trigonal pyramidal

Answer 25

3 ligands, 1 lone pair

Question 26

triple bond

Answer 26

3 bonds (6 electrons) shared between atoms

Question 27

valence electron

Answer 27

electrons in the outermost shell of an atom

Question 28

valence shell electron pair repulsion theory (VESPR theory)

Answer 28

a model used to predict 3-D molecular geometry based on the number of valence shell electron bond pairs among the atoms in a molecule or ion

Question 29

to determine if an atom has a dipole moment

Answer 29

1.) Does the molecule have any polar bonds (bonds with an electronegativity difference greater than 0)
if no, the molecule cannot be polar. If yes, go to 2
2.) Are the bonds symmetrically or asymmetrically aligned in 3D?
symmetric: the polar bonds cancel and molecule is not polar
asymmetric: polar bonds don’t cancel, therefore polar

Question 30

polarity in linear

Answer 30

identical ligands are nonpolar
nonidentical ligands are polar

Question 31

polarity in bend

Answer 31

identical ligands are polar
nonidentical ligands are polar

Question 32

polarity in trigonal planar

Answer 32

identical ligands are nonpolar
nonidentical ligands are polar

Question 33

polarity in tetrahedral

Answer 33

identical ligands are nonpolar
nonidentical ligands are polar

Question 34

polarity in pyramidal

Answer 34

identical ligands are polar
nonidentical ligands are polar

Question 35

2 ligands, 0 lone pairs

Answer 35

linear

Question 36

3 ligands, 0 lone pairs

Answer 36

trigonal planar

Question 37

2 ligands, 2 lone pairs

Answer 37

bent

Question 38

3 ligands, 1 lone pair

Answer 38

trigonal pyramidal

Question 39

4 ligands, 0 lone pairs

Answer 39

tetrahedral

Question 40

ligands

Answer 40

atoms that are not the central atom