n: number of particles that dissociated from the solute molecule.
M.W.: Molecular Weight.
f: osmotic coefficient of the solute
f is given for the concentrations these solutes are encountered in extracellular fluids of mammals.
You can use these values to calculate the osmolarity of physiological solutions.
| Solute |
n |
M.W. |
f |
|
NaCl |
2 |
58.5 |
0.93 |
|
KCl |
2 |
74.6 |
0.92 |
|
HCl |
2 |
36.6 |
0.95 |
|
NH4Cl |
2 |
53.5 |
0.92 |
|
NaHCO3 |
2 |
84.0 |
0.96 |
|
NaNO3 |
2 |
85.0 |
0.90 |
|
KSCN |
2 |
97.2 |
0.91 |
|
KH2PO4 |
2 |
136.0 |
0.87 |
|
CaCl2 |
3 |
111.0 |
0.86 |
|
MgCl2 |
3 |
95.2 |
0.89 |
|
Na2SO4 |
3 |
142.0 |
0.74 |
|
K2SO4 |
3 |
174.0 |
0.74 |
|
MgSO4 |
2 |
120.0 |
0.58 |
|
Glucose |
1 |
180.0 |
1.01 |
|
Sucrose |
1 |
342.0 |
1.02 |
|
Maltose |
1 |
342.0 |
1.01 |
|
Lactose |
1 |
342.0 |
1.01 |