4 - 26 Alcohols
● ***Functional group —OH
●
● ***General formula - CnH2n+1OH
● ***General trend in physical properties:
○ Increase in boiling points
○ Increase in viscosity (粘度)
Oxidation of ethanol (C2H5OH)
● All alcohols burn (combustion, with atmospheric oxygen), forming carbon dioxide and
water, e.g.: ethanol -
C2H5OH (l) + 3O2 (g) → 2CO2 (g) + 3H2O (l)
1
, ● Why does wine left open to the air turn sour?
○ Ethanol in wine oxidised by air, with help of micro-organisms (e.g.:
bacteria/yeast), forming ethanoic acid (CH3COOH)
●
2
● ***Functional group —OH
●
● ***General formula - CnH2n+1OH
● ***General trend in physical properties:
○ Increase in boiling points
○ Increase in viscosity (粘度)
Oxidation of ethanol (C2H5OH)
● All alcohols burn (combustion, with atmospheric oxygen), forming carbon dioxide and
water, e.g.: ethanol -
C2H5OH (l) + 3O2 (g) → 2CO2 (g) + 3H2O (l)
1
, ● Why does wine left open to the air turn sour?
○ Ethanol in wine oxidised by air, with help of micro-organisms (e.g.:
bacteria/yeast), forming ethanoic acid (CH3COOH)
●
2
