Which of the following best describes the primary mechanism by which alum functions as a coagulant?

Alum, typically aluminum sulfate (Al₂(SO₄)₃·14H₂O), functions as a coagulant primarily through the formation of aluminum hydroxide [Al(OH)₃] precipitates. Water often contains suspended particles, including clay, silt, organic matter, and microorganisms. These particles are typically negatively charged and remain dispersed throughout the water due to electrostatic repulsion – like magnets with the same poles, they push each other away, preventing them from clumping together. Alum, when added to water, initially dissociates, releasing aluminum ions (Al³⁺) into the solution. These aluminum ions are positively charged. The aluminum ions then u....