What technique is used for measuring the concentration of dissolved solute particles in a solution?

The technique used for measuring the concentration of dissolved solute particles in a solution is osmometry. This method is specifically designed to determine the osmotic concentration of a solution, which is vital in various clinical and laboratory settings. Osmometry measures the colligative properties of solutions, such as osmosis, which depend on the number of solute particles present rather than their identity.

Osmometers work by assessing factors such as the vapor pressure or freezing point depression of the solution, which correlates directly to the concentration of solute particles. This makes osmometry particularly valuable in situations where understanding the concentration of solutes is critical, such as in assessing serum osmolarity in clinical diagnostics.

The other techniques listed serve different analytical purposes: chromatography is used for separating components in a mixture, densitometry is used for measuring the density of a substance, and electrophoresis is for separating charged molecules based on their size and charge. These methods do not specifically quantify the concentration of dissolved solute particles in the way that osmometry does.