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why is ocean water salty and the river water isn't?
Seawater is salty because rocks contain high levels of sodium (salt) and as they erode, the sodium and other minerals are released in to the water. When water evaporates from the ocean, it rises to the clouds, but only the water rises, not the minerals. The clouds dump the water on land in the form of rain which runs off in to rivers and lakes which makes it fresh water which is filtered by the ground also. It eventually moves back out to the sea. Since the salt does not evaporate, the salt carried from inland rocks as well as those in and around the ocean is also deposited in the, and the amount of salt in the sea just continues to grow more and more. Fresh water does have minerals and salt, but just not concentrated like the sea.


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