Alkanes Flashcards
What does saturated mean
Had no double bonds single bonds only
What are sigma bonds
A bind formed by the lengthways overlap of orbitals directly between 2 bonding atoms
What has sigma bonds
All C-C ,C-H BONDS IN ALKANES
How strong are sigma bonds
Strongest type of covalent bond so high bond enthalpy
What is a consequence of high bond enthalpy
Alkanes are unreactive
What is the bond angle of any carbon in any alkane
109.5
What’s a isomer
Same molecular formula but diff structure
What happens to the boiling points in when carbon chain length increases and why
Boiling point increases because more electrons so stronger London forces require more energy to break
What happens to the boiling points in when there is an increase in branching
Boiling point decreases as less surface area contact so weaker London forces lowering boiling point
What is the order of balancing equations(combustion reactions of alkanes )
C H O
Products of complete combustion
CO2 + H20
Products of incomplete combustion
CO, or C AND water
What can break a covalent bond ( 2 fissions )
Heterolytic and homolytic fission
What is homolytic fission
Each bonding atom receives one electron from covalent bond ( forms 2 radicals )
What is a radical
A species with an unpaired electron
What are the 4 steps in FREE RADICAL SUBSTITUTION
- Initiation -
- Propagation 1
- Propagation 2
- Termination
FORMATION of chloromethane from methane (try to remember all steps )
What happens if there is excess of the halogen
Further substitution
