15.1 Chemistry of Haloalkanes Flashcards
(18 cards)
What is a haloalkane?
An alkane containing at least one halogen
Are haloalkanes polar or non-polar? Why?
Polar, they have a carbon-halogen bond in their structure, and the halogen is more electronegative than the carbon, so the bond is polar.
Are haloalkanes soluble or insoluble? Why?
Insoluble, they cannot form hydrogen bonds with water.
What is a nucleophile?
A species that donates a lone pair of electrons.
What happens when a haloalkane reacts with a nucleophile?
The nucleophile replaces the halogen in a substitution reaction.
What is the name of the reaction involving a nucleophile displacing the halogen group?
Nucleophilic substitution.
Describe the steps of nucleophilic substitution.
1- Nucleophile approaches the carbon atom attached to the halogen on the opposite side of the molecule from the halogen
2- Lone pair of electrons on nucleophile is attracted and donated to the delta positive carbon atom.
3- A new bond is formed between the nucleophile and the carbon atom
4- Carbon-halogen bond breaks by heterolytic fission
5- 2 new products formed.
How can haloalkanes be converted to alcohols?
By reacting them with aqueous sodium hydroxide, and reacting them under reflux.
What does the rate of hydrolysis in a nucleophilic substitution depend on?
The strength of the carbon-halogen bonds in the haloalkane.
Describe the trend of the strength of carbon-halogen bonds as you go down group 7.
As you go down the group, the bond enthalpy for the carbon-halogen bond decreases.
Which haloalkane is unreactive?
Fluroalkanes.
State the equation for the hydrolysis of a primary haloalkane (in this case halobutane)
CH3CH2CH2CH2X + H2O –> CH3CH2CH2CH2OH +H+ + X-
What chemical allows water and haloalkanes to mix?
Ethanol.
Why is ethanol added to make haloalkanes and water mix?
Because it dissolves both of them.
What is a homogeneous catalyst?
A catalyst that is the same state of matter as the reactants in a chemical reaction
What is a radical?
A species with an unpaired valence electron
If you can use a gas to blow out a flame, what is one of the properties of said gas?
It is non-flammable
How is nitrogen monoxide formed?
When nitrogen and oxygen from the atmosphere enter an engine, where they react under high temperatures and pressure.
