Inductive, Resonance and Hyperconjugative Effects
Inductive effects transmit polarity through σ bonds, resonance delocalises π electrons, and hyperconjugation delocalises σ electrons into adjacent empty or π orbitals.
What is Inductive, Resonance and Hyperconjugative Effects?
Inductive effects transmit polarity through σ bonds, resonance delocalises π electrons, and hyperconjugation delocalises σ electrons into adjacent empty or π orbitals.
Key formula / rule: Inductive effects weaken rapidly with distance along a chain.
Key points
- Compare inductive and resonance effects in a substituted molecule.
- Apply electronic effects to explain relative acidity or basicity.
Common exam trap
Drawing resonance structures that move atoms rather than electrons.
Definitions
- Term
Inductive, Resonance and Hyperconjugative Effects
- Meaning
Inductive effects transmit polarity through σ bonds, resonance delocalises π electrons, and hyperconjugation delocalises σ electrons into adjacent empty or π orbitals.
- Term
Inductive, Resonance and Hyperconjugative Effects — explanation
- Meaning
These three effects explain acidity, basicity and reactivity ordering throughout organic chemistry. Resonance is generally stronger than induction and does not fade with distance.
Learning objectives
Compare inductive and resonance effects in a substituted molecule.
Apply electronic effects to explain relative acidity or basicity.
Formulae
- Key point
Inductive effects weaken rapidly with distance along a chain.
- Key point
Resonance requires conjugation and planarity.
- Key point
Hyperconjugation stabilises carbocations and alkenes with more α hydrogens.
Prerequisites
CHE-U4-GO-T1-S1-C2
Common mistakes
Drawing resonance structures that move atoms rather than electrons.
Applying resonance to a system that is not conjugated.
Keywords
Inductive
Resonance
Hyperconjugative
Effects
Practice preview
What is the primary characteristic of the resonance effect?…
easy
Hyperconjugation is also known as:…
easy
Which of the following carbocations is most stable due to hyperconjugation?…
medium