Lewis Dot Structures

Ch1a Extra Practice with Lewis Dot and Resonance Structures

Supplemental Materials

Draw Lewis structures for the molecules below. Draw resonance structures where appropriate and label any formal charges. Rank resonance structures in order of importance to overall structure.

1.) 2.) 3.) 4.) 5.) 6.) 7.) 8.) 9.) 10.) 11.)

[SCN][HC2O4]SNF3 [S2CO]2[IO3][HCO3]PF3 [SO4]2[C3H5]+ [S3N3]- (cyclic, every other atom is S) [ClO4](C is central)

Page 1 of 1

Worksheet for Lewis Structures, Resonance Structures, and Formal Charge Solutions

1.)

S

C

N

S

C

N

There are two things to consider here. The structure on the left gives N three bonds which is good, the structure on the right puts the formal negative charge on the more electronegative element. My guess is that the left structure is more important because N really likes to have 3 bonds.

O O C

O C

H O O

O C

O C

H O

2.)

These are equally important.

N F

S
F

F

3.)

4.)

O S

O S S

O S S

C

C

C

S

The right two structures are equally important and probably more important than the left structure (negative charge on more electronegative atom).

5.)

O O

O O O

O O O

I

I

I

O

O O

O O O I O O

O

I

I

O

The top three are equally important. The first two on the bottom are of equal importance. I think the bottom right two will be most important (fewer formal charges), then maybe

the bottom left structure (maximize bonding), then the top three structures. The order of importance isn’t entirely clear between the last two groups. (Argument between maximize bonding and put negative charge on the more electronegative atom.)

O O

H O O

O

H O

6.)

C

C

These two structures are equally important.

F

P
F

F

7.)

8.)

O O

O O O

O O O

S
O

S
O

S
O

O

O