Gesamtkonzentration

Gesamtkonzentration describes the total concentration of all dissolved substances in a solution. It is usually expressed in mol/L (molarity) and is defined as the sum of the molar concentrations of all dissolved species present in the solution: c_tot = Σ_i c_i, where c_i is the molar concentration of species i.

In practice, how c_tot is interpreted depends on the context. For non-electrolytes such as sugars or poorly dissociating solutes, c_tot is simply the sum of their molar concentrations. For electrolytes that dissociate in solution, there is a choice: one can sum the concentrations of the formula units (e.g., 0.10 M NaCl contributes 0.10 M to c_tot), or one can sum the concentrations of all resulting particles (e.g., Na+ and Cl− would together contribute 0.20 M). In many formulation and analytical contexts, the focus is on the amount of dissolved substance per liter, and c_tot is used as a descriptive shorthand.

Applications include product formulation, quality control, and process design, where knowing the overall load of dissolved material helps assess effects on viscosity, freezing point depression, or osmotic pressure. The term is not a strictly defined thermodynamic quantity like osmolarity or ionic strength, but is common in applied chemistry and pharmaceutical contexts.

Example: a solution with 0.10 M NaCl and 0.05 M glucose has c_tot = 0.15 M when counting formula units; if one tracks osmotically active particles (assuming full dissociation), c_tot may differ.