Reasonance & Organic Acid-Base Chem Flashcards
What is resonance?
Reasonance is a way of describing delocalized electrons within molecules/polyatomic ions where bonding cannot be represented by a single Lewis formula.
Reasonance: shows the movement/spreading of electrons across a structure
Reasonance is NOT a process
What are minor reasonance structures?
All the reasonance structures that are higher in energy than the lowest-energy contributor
This question refers to Major Reasonance structures. Fill in the blanks
1) It has the ________ energy
2) Generally have all octets satisfied
3) Minimal charge separation
4) Negative charges are more stable on ____________ atoms
1) It has the lowest energy
2) Generally have all octets satisfied
3) Minimal charge separation
4) Negative charges are more stable on the more electronegative atoms
Electronegativity: F > O > Cl > N > C
In reasonance structures; electrons can be moved around
I) From a lone pair to become a pi bond
II) From a pi bond to become a lone pair
III) From a lone pair to become a single bond
IV) From a pi bond to become another pi bond
I) From a lone pair to become a pi bond
II) From a pi bond to become a lone pair
IV) From a pi bond to become another pi bond
The number of unpaired electrons must remain the same
What class of dienes does this statement refer to?
Has two successive double bonds on adjacent carbond.
C=C separated by one C-C within structure.
Conjugated Diene
What class of dienes does this statement refer to?
Has 2 successive double bonds on adjacent carbons.
C=C one behind the other in structure of diene
Cumulated Dienes
They’re also called Allenes
What class of dienes does this statement refer to?
Has 2 double bonds separated by two or more carbon-carbon single bonds.
C-C=C-C-C-C-C=C-C
Isolated diene
Which class of diene is most stable?
I) Cumulated
II) Conjugated
III) Isolated
II) Conjugated
Conjugated Dienes are more stable than non-conjugated dienes.
What is a Lewis Acid?
Lewis Acids are electron pair acceptors
Electrophile
Lewis Acids/Bases looks at Electron movement
What is a Lewis Base?
Lewis Bases are electron pair donors
Nucleophile
Lewis Acid/Bases looks at electron movement
What is a Brønsted–Lowry Acid?
A Brønsted–Lowry Acid is a proton donor
Brønsted–Lowry looks at proton (H+) movement
What is a Brønsted–Lowry Base
A Brønsted–Lowry Base is a proton acceptor
Brønsted–Lowry looks at H movement
Which theory defines acids as substances that dissociate in water to give hydroniumions?
Arrhenius Theory
Stronger acids dissociated to a greater degree than weaker acids
What does Arrhenius theory define bases as?
Substances that dissociate in water to give hydroxide ions
