Organic Chemistry with Oxygen Flashcards
Factfile for alcohols
Must contain OH
general formula: C(n)H(2n+1)OH
Suffix: anol
What are the reactants and conditions for making ethanol by fermentation?
Reagents: sugar, water
Conditions: 37 degrees, yeast, anaerobic
What are the reactants and conditions for making ethanol by direct hydration?
Reagents: ethane, steam
Conditions: 60-70 atmospheres, 300 degrees, phosphoric acid
What are the advantages and disadvantages of fermentation?
Ad: renewable resource, cheap equipment, low energy cost
Dis: slow, only 15% yield, batch process
What are the advantages and disadvantages of the direct hydration method?
Ad: fast, nearly 100% yield and pure, continuous process
Dis: finite resources, expensive equipment, high energy cost
What is distillation?
Evaporation followed by condensation
What is distillation used for?
Making high percentage ethanol without direct hydration
Makes whiskey/vodka and car ethanol
How is ethanol oxidised (2 ways)?
1) by the presence of air and bacteria (microbial oxidation)
2) by heating with potassium dichromate solution (K2Cr2O7) and sulphuric acid (goes orange to green)
Factfile for carboxylic acids
Must contain COOH General formula C(n)H(2n-1)OOH Suffix: anoic acid Made by oxidation of alcohols Weak acids as not much dissociation
Factfile for esters
Must contain COO
H2O always formed with it
OH from the carboxylic acid removed . Acid always on left.
Used in flavourings and perfumes
How are esters made?
Made by reacting an alcohol with a carboxylic acid with concentrated sulphuric acid as a catalyst.
Conditions: warmth
Sodium carbonate solution neutralises remaining acid and esters insoluble in water so floats
What is condensation polymerisation?
When 2 different monomers (dicarboxylic acid and a dialcohol) bond together.
An Ester repeat unit
Forms water always
