Chpt 2: Molecular Representations (Resonance and Stuff)

Question 1

in a resonance structure, if you see an arrow pointing from a double bond to a single bond, what should you do?

Answer 1

Draw a double bond where the arrow head is pointing

And erase the double bond where the arrow tail is coming from

Question 2

in a resonance structure, if you see an arrow pointing from a double bond to an atom, what should you do?

Answer 2

draw a lone pair on the atom where the arrow head is pointing

And erase the double bond where the arrow tail is coming from

Question 3

what 2 rules can you never break when drawing a resonance structure?

Answer 3

1. you can’t break the octet rules

2. you can’t break any single bonds

Question 4

when you see a pi bond and a positive charge separated by a single bond, how will the pi bond behave to make resonance?

Answer 4

the pi bond will always move towards the positive charge (eliminating it), and leave a new positive charge in its wake

Question 5

when you see a lone pair and a positive charge separated by a single bond, how will the lone pair behave to make resonance?

Answer 5

the lone pair will always move towards the positive charge (eliminating it), and leave an appropriately updated charge on the atom it came from

Question 6

when you see a pi bond between atoms of differing electronegativities, how will the pi bond behave to make resonance?

Answer 6

the pi bond will move to the more electronegative atom, in the form of lone pair, which may give a negative charge to the receiving atom and a positive charge on the atom the pi bond came from