What you are given
- Solutes: [{"name":"NaCl","conc_mM":"150","particles":"2"},{"name":"Glucose","conc_mM":"5","particles":"1"}]
Formula: mOsm = sum(mM x particles)
Physical
How do you calculate osmolarity?
Total osmolarity of a multi-solute solution. The relationship used is mOsm = sum(mM x particles).
Worked example
Every number below is computed by the calculator, not typed in
The working
- Contribution of NaCl:
150 mM · 2 = 300 mOsm=300 mOsm - Contribution of Glucose:
5 mM · 1 = 5 mOsm=5 mOsm - Total osmolarity:
mOsm = Σ (conc_mM · particles)=305 mOsm
Total osmolarity is 305 mOsm/L.
What each symbol means
- mOsm: Total osmolarity (mOsm/L)
- Cᵢ: Concentration of solute i (mM)
- νᵢ: Osmotically active particles of solute i (van't Hoff factor)
A printable one-page version is on the formula sheet.
Do it with your own numbers.
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