4.2.2 Haloalkanes Flashcards
What are chloroethanes used for
Dry cleaning
What’s dichloromethane
A solvent in industry
What’s chloroform
An old fashioned anaesthetic
What have chlorofluorocarbons been used as in the past even though they’re now banned
Aerosol propellants + in fridges
What do chlorofluorocarbons damage
How
The ozone layer (O3)
When they decompose they produce very reactive Cl free radicals that destroy ozone molecules
What’s the ozone layer
Layer in atmosphere that absorbs UV radiation (chemical sunscreen)
3 factors of chlorofluorocarbons
Stable
Volatile
Non-flammable
Non-toxic
2 processes that generate Cl radical from chlorofluorocarbon
Homolytic fission
Initiation (UV light)
What does the greenhouse affect cause
The atmosphere to trap heat radiating from Earth towards space.
4 reasons global warming is a problem
- sea levels rising causing flooding
- rainfall less reliable
- more droughts + heatwaves
- hurricanes stronger and more intense
- arctic ice melting
2 ways governments are working to limit global warming
- reduce tropical deforestation
- expand renewable energy use
- increase vehicle fuel efficiency
- place limits on amounts of emissions allowed
What’s the process called to break a polar bond
Heterolytic fission
What’s the d+ Carbon open to attack from in a polar bond
Nucleophiles (electron rich species)
Define nucleophile
Species that donates a lone pair of electrons
What is the mechanism type here
Nucleophilic substitution reactions of haloalkanes
