4) Nonpolar solids are insoluble in polar solvents.
5) Nonpolar liquids are usually mutually miscible.
6) Nonpolar liquids and polar liquids do not mix.
- Methanol (ethanol, and propanol) and water are miscible in all proportions.
O
δ−O
H 3 CH 2 C H
H H
δ+
δ+ δ+
δ− Hydrogen bond
1) Alcohol with long carbon chain is much less soluble in water.
2) The long carbon chain of decyl alcohol is hydrophobic (hydro, water; phobic,
fearing or avoiding –– “water avoiding”.
3) The OH group is hydrophilic (philic, loving or seeking –– “water seeking”.
CH 3 CH 2 CH 2 CH 2 CH 2 CH 2 CH 2 CH 2 CH 2 CH 2
Hydrophobicportion
Decyl alcohol
OH
Hydrophilic group
2.14F GUIDELINES FOR WATER SOLUBILITIES
- Water soluble: at least 3 g of the organic compound dissolves in 100 mL of water.
- Compounds containing one hydrophilic group: 1-3 carbons are water soluble;
4-5 carbons are borderline; 6 carbons or more are insoluble.
2.14G INTERMOLECULAR FORCES IN BIOCHEMISTRY
