3. Osmotic pressure of body fluid (plasma) Positive ion 151mmoVL Negative ion: 139 mmol/L /total 280-310mmol/L Nonelectrolyte: 10mmol/L (678.3kpa) Plasma colloidal osmotic pressure 3.72kpa(28mmHg3. Osmotic pressure of body fluid (plasma) Positive ion: 151mmol/L Negative ion: 139mmol/L total 280-310mmol/L Nonelectrolyte: 10mmol/L (678.3kpa) Plasma colloidal osmotic pressure: 3.72kpa(28mmHg)