3.1 Molecular Orbitals Flashcards
How are molecular orbitals generated
By combining atomic orbitals
what can molecular orbital theory be used to describe
how atomic orbitals merge and overlap when atoms bond to form molecules
What 2 types of orbitals are formed when two atomic orbitals combine
2 molecular orbitals, one bonding and one anti-bonding
How are sigma bons formed
when there is ‘end-on’ overlap between atomic orbitals
How are pi bonds formed
When there is ‘side-on’ overlap between atomic orbitals
When do pi bonds arise
When atoms form multiple bonds
What can be used to explain why carbon adopts a tetrahedral structure
Hybridisation
What is hybridisation
The process of mixing atomic orbitals within an atom to generate a set of new atomic orbitals called hybrid orbitals
What kind of hybridisation is in alkanes
sp3
What kind of hybridisation is in alkenes and benzene rings
sp2
Why are sigma bonds stronger than pi bonds
because they are more efficient at overlapping
What kind of hybridisation is in alkynes
sp
What is a conjugated system
When a molecule has alternating single and double bonds
What is the chromophore
The part of a molecule responsible for its colour. It is the largest part of a molecule involving a conjugated system.
Higher degree of conjugation
Smaller energy gap, lower energy, longer wavelength
