What can chemical emulsions be removed by?

Chemical emulsions, which are mixtures of two immiscible liquids, can indeed be removed using a variety of methods, making "All of the above" the correct choice.

Additives can be employed to break the emulsion by altering the properties of the liquids involved. This may include adding surfactants that reduce the surface tension or coagulants that cause the dispersed phase to clump together and separate more easily.

Gravity plays a significant role in separating emulsions, particularly when there are differences in density between the two liquids. Over time, the lighter component can rise to the surface while the heavier one settles to the bottom, allowing for initial separation.

Settling or centrifugal action is particularly effective in removing emulsions, as these processes enhance the separation of the different phases. Settling relies on gravity to allow the components to separate naturally, while centrifugal action uses force generated by spinning to accelerate the separation process, making it more efficient.

Together, these methods provide a comprehensive approach to effectively removing chemical emulsions from a mixture. Thus, the option that includes all the various methods is appropriate.