hat name is given to the process by which a dissolved substance moves across a boundary to an area of lower concentration?

The process by which a dissolved substance moves across a membrane or boundary to an area of lower concentration is called diffusion. Diffusion occurs as molecules spontaneously move from regions of higher concentration to regions of lower concentration, ultimately resulting in an even distribution of the substance throughout the available space.

This process is driven by the random motion of particles and continues until equilibrium is reached, meaning the concentrations on both sides of the boundary are equal. Diffusion is a fundamental concept in various fields including chemistry, biology, and physics, as it explains how substances mix and move in solutions, gases, and even across cell membranes.