Understanding the Units

* mg/L: Milligrams per liter, a measure of mass concentration.

* meq/L: Milliequivalents per liter, a measure of chemical activity or the ability of a substance to react.

Conversion Factors

* Atomic weight of Sodium (Na): 22.99 g/mol

* Valence of Sodium: 1 (Sodium has a +1 charge)

* Conversion factor: 1 g = 1000 mg

* Conversion factor: 1 mol = 1000 mmol

Calculation Steps

1. Convert mg/L to g/L:

73.6 mg/L * (1 g / 1000 mg) = 0.0736 g/L

2. Convert g/L to mmol/L:

0.0736 g/L * (1 mol / 22.99 g) * (1000 mmol / 1 mol) = 3.20 mmol/L

3. Convert mmol/L to meq/L:

3.20 mmol/L * (1 meq / 1 mmol) = 3.20 meq/L

Therefore, 73.6 mg/L of Sodium is equivalent to 3.20 meq/L.