Why isn’t the ocean fresh water?
In: Chemistry
Because it is continually refilled by rivers, as well as rain.
Rivers erode rocks and carry salts downstream with them. The ocean is the ultimate “downstream”, where everything accumulates. Once the salts are in the water, it is hard to remove them. It is especially hard to remove them when more salt is being added all the time. The oceans are very, very, very old and have had a long time to accumulate salts.
Ponds and lakes are much younger than the oceans and have more rainfall refill compared to the oceans.
For examples of waterbodies getting salty/brackish over time, look up the Aral Sea and the Salton Sea. Great Salt Lake is another interesting example where there is a lot of evaporation, but little rainfall, resulting in a salty inland waterbody.
Latest Answers