Chapter 14 and 15 - Alcohols and Haloalkanes Flashcards
Why do alcohols have much higher boiling points than alkanes?
They have an OH group so they can form hydrogen bonds that require extra energy to be broken.
Why are alcohols soluble in water?
The polar OH bond forms hydrogen bonds with the water molecules.
As chain increases, how does solubility of alcohols change?
It decreases as the OH group’s influence becomes smaller.
Are alcohols polar?
Yes because they have a polar OH bond.
What is a nucleophile?
Species that donates a lone pair of electrons
Give 3 examples of nucleophiles.
Water, H2O
Hydroxide ions, OH-
Ammonia, NH3
What effects the rate of hydrolysis in haloalkanes?
The strength of the carbon-halogen bond.
What is the trend in rate of hydrolysis down the halogen group and why?
Down the group rate of hydrolysis increases because bond enthalpy decreases so less energy is required to break the carbon-halogen bond.
What is the equation of hydrolysis of haloalkanes with water?
CH3-X + H2O —> CH3OH + X- + H+
How can the rate of reaction be followed in hydrolysis of a haloalkane?
React with Ag+ ions to form halide precipitate.
Ag+(aq) + X-(aq) —> AgX(s)
What is the nucleophile in the reaction of haloalkanes with Ag+ ions?
Water which is present in the aqueous AgNO3.
Why is the hydrolysis reaction of haloalkanes carried out in ethanol solvent?
Because haloalkanes are insoluble in water, so ethanol allows water and the haloalkane to mix and produce a single solution rather than 2 layers.
