<u>Answer:</u> The given reaction is a "Dehydration Synthesis Reaction".
<u>Explanation:</u>
In chemical science the antonym of hydration is dehydration reaction which is a common process of conversion take place by involving loss of water from reacting molecule or ion. For an instance the dehydration process help in formation of disaccharide (sucrose) from two monosaccharides (glucose + fructose) as given in reaction.
Some other examples are like conversion of an acid and an alcohol into an ester and reaction called as "Fischer–Speier esterification", Conversion of an alcohol to alkene etc. Normally dehydration is followed by heating or leaving at room temperature, although it is a time taking process. Some common dehydrating agents are like alumina and sulfuric acid for organic synthesis.
Explanation:
The depth is remaining constant in the surface layer, so that indicates the surface layer is. well mixed. C. The salinity is fairly constant in the surface layer, so that would indicate the layer is well. mixed