This is a very wide ranging question, as the answer depends entirely on what element or substance it is we are talking about.
Generally, ionic compounds split up into their ions and then these ions may react with other ions present in the ocean, to form a solid. This new solid precipitates from solution and sinks to the ocean floor.
Gases dissolved in the water will also react with ions. There is a general chemical tendancy that if two substances which are soluble can react to form a solid, they will do so. As the ocean can contain a huge number of substances, partly due to polution, there are a huge number of possible reactions that can occur.
When any solids formed sink to the bottom, they can then form the silt or mud that covers the ocean floor. Some solids can re-dissolve a little bit and then precipitate out again. This tends to form larger lumps of some substances over a long period of time.
Generally, ionic compounds split up into their ions and then these ions may react with other ions present in the ocean, to form a solid. This new solid precipitates from solution and sinks to the ocean floor.
Gases dissolved in the water will also react with ions. There is a general chemical tendancy that if two substances which are soluble can react to form a solid, they will do so. As the ocean can contain a huge number of substances, partly due to polution, there are a huge number of possible reactions that can occur.
When any solids formed sink to the bottom, they can then form the silt or mud that covers the ocean floor. Some solids can re-dissolve a little bit and then precipitate out again. This tends to form larger lumps of some substances over a long period of time.