Alcohols Flashcards
what is the general formula of alcohols?
CnH2n+1
what is the functional group of alcohols?
-OH
how are alcohols classified?
primary/ secondary/ tertiary
do alcohols have high or low mp/bp?
generally high bp due to addition of hydrogen bonding as well as permanent dipole-dipole
how does bp trend with size of alcohols?
as they get bigger, the bp increases due to more Van der Waals forces
what is the solubility of lower mass alcohols?
they are miscible with water because of hydrogen bonding
what is the solubility of higher mass alcohols?
they are not soluble because non-polar nature of hydrocarbon dominates
name two ways that ethanol is produced
- fermentation
- hydration of ethene
what are the conditions for fermentations and why?
- no air so that ethanol isnt oxidised to ethanoic acid
- therefore anaerobic respiration
- enzymes from yeast
- warm temp of 35oC
why is the ethanol produced from fermentation classed as a biofuel?
because it is a fuel produced from a renewable biological source
why is it termed as carbon neutral?
carbon released when burnt equals carbon absorbed from photosynthesis
why is it being carbon-neutral not necessarily true?
- carbon costs from transporting crops and fuel for producing ethanol
what is the catalyst for hydration of ethene? and what are the conditions?
phosphoric acid
- 300oC/ 70 Mpa (high temp/pressure)
name three types of reactions with alcohols
- combustion
- elimination
- dehydration
name a type of fuel that ethanol is used in
methylated spirits - small percentage of methanol as well. Since methanol is poisonous, it cannot be drunk so purple dye is added and hence no tax
