salinity
saltwater has salt in it, freshwater does not.
No Oceans are not Freshwater, they are salt water
Salt in the water. Salt water.
Ocean water has salt in it, Freshwater does not.
All ground water is freshwater. But not all freshwater is in the form of groundwater. E.g. freshwater may exist in the form of ponds, lakes, rivers or ice caps.
No. Lake water is freshwater and ocean water is saltwater.
Salt in the water. Salt water.
The difference in bodies of water is usually where they are located and the type of water they contain. The difference between a sea and ocean is just that a sea is attached to an ocean and surrounded by land. A lake is usually freshwater and located in a natural depression while a river usually flows over a long distance one way.
Maybe that saltwater animal can endure hard water and freshwater animals can't.
Yes; rivers run into the ocean at places called Estuaries. What evaporates from the ocean, and is dropped as freshwater in raindrops.
Where a freshwater river drains into an ocean, the fresh water may mix with the salt water ... this is called brackish water.
An ocean is a large body of water. You look at what you 'see'.