6.4 Flashcards
what is the general formula for alcohols
CnH2n+1OH
describe chlorination
use phosphorous chloride
vigorous at room temperature
describe chlorination of tertiary alcohols
mix with concentrated HCl at room temperature
describe bromination
use potassium bromide and 50% concentrated sulfuric acid
describe iodination
use red phosphorus and iodine
heat under reflux
describe dehydration to alkenes
heating the alcohol with phosphoric acid
define ketones
a homologous series of organic compounds formed by oxidation of secondary alcohol
define aldehyde
homologous series of organic compounds formed by the partial oxidation of primary alcohols
is a ketone or an aldehyde more easily oxidized
aldehyde
what is an aldehyde oxidized to
carboxylic acid
define carboxylic acid
homologous series of organic compounds formed by the complete oxidation of primary alcohols
what do primary and secondary alcohols form when they are oxidized
secondary alcohol -> ketone
primary alcohol -> aldehyde -> carboxylic acid
what are the reagents for oxidation of alcohols and how are they represented in an equation
potassium dichromate (VI)
dilute sulfuric acid
[O]
colour change - orange -> green
what is heating under reflux
heating a reaction mixture with a condenser fitted vertically
what is distillation with addition
heating a reaction mixture but adding another liquid and distilling off the product as it forms
what could be contaminating organic compounds
unreacted starting materials
other organic compounds
inorganic reagents
inorganic products
water
what techniques can be used to purify an organic mixture
simple distillation
fractional distillation
solvent extraction
drying
what are the issues with doing practical’s with organic substances
flammable
toxic
increased risk of leaks and contamination
define simple distillation
used to separate liquids with very different boiling temperatures
summarize simple distillation
heat in flask with condenser
lowest bp evaporates first and is passed to the condenser
thermometer monitors temperature
if temp remains steady a compound is being distilled
define fractional distillation
used to separate liquids with similar boiling temperatures
summarize fractional distillation
same apparatus as simple distillation with a fractionating column filled with glass beads so the vapor can condense and evaporate repeatedly which provides better separation
define solvent extraction
used to separate a liquid from a mixture by causing it to move from the mixture to the solvent
what does immiscible mean
doesn’t mix
summarize solvent extraction
place reaction mixture in a separating funnel
stopper and gently shake
allow contents to settle
open tap and allow the lower layer to drain
state some good drying agents and why they are effective
anhydrogenous salts (calcium sulfate, magnesium sulfate, calcium chloride)
doesn’t react with the organic compound
adsorbs the water as water of crystallization forming a hydrated salt
summarize drying
drying agent added, swirled and left for a period of time
drying agent goes from powdery to crystalline and when the organic liquid has been dried more drying agent can be added and it will stay a powder
drying agent is removed by filtration on decantation
how do impurities effect boiling points
more impurities the higher the bp
