Chapter 8 part 2

Question 1

single bond

Answer 1

one pair of electrons is shared

Question 2

double bond

Answer 2

2 pairs of electrons are shared

Question 3

triple bond

Answer 3

3 pairs of electrons are shared

Question 4

what is the trend with bond length and number of shared electrons

Answer 4

bond length shortens as number of shared electrons increase

Question 5

energy required to break a bond

Answer 5

endothermic

Question 6

energy released when bond formed

Answer 6

exothermic

Question 7

lone pair

Answer 7

pairs of electrons localized on an atom
- only on an atom

Question 8

bonding pairs

Answer 8

pairs of electrons found in space between atoms
- shared

Question 9

what is the difference between lone and bonding pairs

Answer 9

bonding pair is shared between two atoms while lone pair belongs only to the atom which it is assigned

Question 10

when does a Lewis dot structure not apply

Answer 10

ionically bonded compounds

Question 11

how are electrons shared

Answer 11

between covalent and polar covalent bonds so each atom has a noble gas like e- configuration

Question 12

what rule applies to hydrogen

Answer 12

duet

Question 13

what elements does the octet rule apply to

Answer 13

C, N, O, F, and sometimes other non-metallic elements in the p block

Question 14

which Lewis dot structure will be correct when there are multiple versions

Answer 14

one with minimized formal charges

Question 15

duet rule

Answer 15

shares 2 electrons

Question 16

octet rule

Answer 16

surrounded by 8 electrons

Question 17

what are the rules to drawing a Lewis structure

Answer 17

1. add valence electrons from all atoms
2. use pair of electrons to form bond between each pair of bound atoms
3. arrange remaining electrons to satisfy the duet and octet rule

Question 18

when is an atom more stable

Answer 18

when it is more negative

Question 19

what are reactants

Answer 19

bonds broken

Question 20

what are products

Answer 20

bonds formed

Question 21

what are some of the exceptions of the octet

Answer 21

boron
beryllium
sulfur hexafluoride

Question 22

boron exception

Answer 22

forms 3 bonds
less than 8 electrons
electron deficient

Question 23

beryllium exception

Answer 23

less than 8 electrons (2e-)
electron deficient

Question 24

sulfur hexafluoride exception

Answer 24

more than 8 electrons

Question 25

what elements have an expanded octet

Answer 25

those elements in the 3rd period and greater

Question 26

resonance

Answer 26

more than 2 valid lewis dot structure can be written

Question 27

what are some important aspects to a resonance structure

Answer 27

• double headed arrow
• bond lengths the same
• resulting structure is average of resonance structure

Question 28

odd electron molecules

Answer 28

• uncommon
• few molecules formed from nonmetals have odd # e-
• very reactive

Question 29

what is the difference in length between single and double bonds

Answer 29

double bonds are a little shorter than single bonds

Question 30

formal charge

Answer 30

(-)= more EN
(+)= less EN

Question 31

what are the rules to formal charge

Answer 31

• bonds count as 1 electron
• lone pairs count as 2 electrons
• tend to reside on most EN atom

Question 32

what is the equation for formal charge

Answer 32

valence electrons - (# bonding electrons/2) + # lone pair electrons