Chem Quiz #3

Question 1

Core e-

Answer 1

e- in inner shells that don’t participate in chemical reactions

Question 2

Valence Isoelectronic

Answer 2

atoms in some period group w/ same # of valence e-

Question 3

G.N. Lewis

Answer 3

introduced cubicle atoms & knew of core e- & that there are 8 valence e- in an octet

Question 4

Octet Rule w/ exception

Answer 4

atoms combine to achieve filled shells (octets) of e- & have structures that are isoelectronic w/ noble gases
Exception: hydrogen (duet) & transition elements (18 e- rule)

Question 5

Lewis Structures

Answer 5

assumes molecule is composed of atoms bound together w/ atomic orbitals to share e- pairs

Question 6

BH3

Answer 6

only has 3 valence e- & doesn’t have an octet configuration (sextet) (electronically unsaturated)
HYPOvalent

Question 7

Empty Orbital

Answer 7

Space around atom where B in BH3 would LOVE to form a pair

Question 8

Orbitals

Answer 8

Place to put e-

Question 9

Elements ____ of Carbon have empty orbitals

Answer 9

left

Question 10

Elements ____ of Carbon have filled orbitals (lone pairs)

Answer 10

right

Question 11

Dative/Coordinate Covalent Bonds w/ ex

Answer 11

single atom provides both e-
donor acceptor bond
ex. N in NH3 provides e- to bond NH3 w/ BH3

Question 12

How to calc. formal charge

Answer 12

Formal Charge = group valence - #e- in lone pairs - # bonds

Question 13

Dative Covalent Bond

Answer 13

forms w/ Lewis Acid (A) & Lewis Base (B)

Question 14

arrow between bonds indicates
ex. N-B

Answer 14

N has (+) formal charge and B has (-) formal charge

Question 15

e- pair acceptor

Answer 15

Lewis Acid

Question 16

e- pair donor

Answer 16

Lewis Base

Question 17

how to calc. # e- in central atom?

Answer 17

group valence - nearest multiple of 8

ex. 03 has 18e- and nearest multiple of 8 is 16 soooo 18-16=2e- in middle atom

Question 18

Formal Charge

Answer 18

Formal Charge = group valence - #e- lone pairs - # bonds

Question 19

Dipole Moment of CO

Answer 19

carbon is (-) even tho oxygen is more electron(-)

Question 20

CO & N2 are isoelectronic & both have triple bonds butt

Answer 20

N2 doesn’t have any formal charges

Answer 21

formal charges or dative bonds should always be incorporated when representing the bonding in molecules

Question 22

how to calc #e- in valence shell

Answer 22

e- in valence shell = # valence e- in neutral atom + #bonds - formal charge

Question 23

Resonance Structures

Answer 23

differ in e- position & not nuclei position

Question 24

Bond order in O3

Answer 24

O-O=O has bond order of 1.5

Question 25

Benzene

Answer 25

resonance…sometimes drawn w/ circle since bonding can’t be properly represented by lewis structure
- line = shared e- pair bond

Question 26

Equivalent Resonance Structures

Answer 26

have same energy

Question 27

Degenerate

Answer 27

are symmetrical & have same energy