Question

3. (10%) The anion deficit in water can be used to estimate the charge content of dissolved organic matter (DOM) assuming that all significant ions have been measured and are accurate. In a water with DOC = 8 mg C / L and an anion deficit of 35 μequiv / L, calculate the charge content of the DOM in mmol of charge / g C.

Answer 1

The anion deficit is a value calculated from the results of multiple individual medical lab tests. It may be reported with the results of an Electrolyte Panel, which is often performed as part of a Comprehensive Metabolic Panel.

The anion deficit is the difference between the measured cations (positively charged ions) and the measured anions (negatively charged ions) in serum, plasma, or urine. The magnitude of this difference in the serum is often calculated in medicine when attempting to identify the cause of metabolic acidosis, a lower than normal pH in the blood. If the gap is greater than normal, then high anion gap metabolic acidosis is diagnosed.

here anion deficit of the water will be

anion deficit = H+ - [ OH-] = 35 uequiv/L

Dissolved organic carbon (DOC) = 8 mgC/L

since we will have dissolved oxygen in the solution, which will further contribute to charge content ,

charge content of DOM = anion deficit / DOC

= 35/8 mmol of charge / gC