What is the purpose of the oceans being salty?

Question

......just wondering if the vast majority of the globe is water, and water sustains life.....then the oceans waters are not fit for human comsumption, were they ever fresh water, and if so what brought about the change?

Answer 1

It is not a question of having a purpose, but of how oceans evolved to be salty.

Oceans are salty as a result of their age and because of erosion processes on the continents. When rain falls on the continents, the acid in the rain dissolves certain atoms (like iron, magnesium, sodium, potassium) from ground rock, and these dissolved materials are transported eventually (in many cases) to the oceans. When this water evaporates, it leaves the dissolved load in the oceans, so that over time the oceans gain a larger and larger amount of dissolved material.

The study of the chemistry of oceans is interesting and complicated, requiring us to consider also the interaction of the ocean with the materials in the crust of the ocean.

But the short answer to your question is that the "salt" (which really means lots of different types of dissolved atoms) comes from the continents; rivers and lakes are not old enough to be as "salty" as the oceans.

In fact, one of the first ways to estimate the age of the Earth was to figure out how long it would take for the oceans to get as salty as they are.

Answer 2

seawater taste salty because it has salt in it!the salt as the same as the stuff that people sprincle on food.most of it comes from rocks on the land.rain washes the salt into rivers which carry to the sea.mast of water in earth is salty.only tiny parts is fresh water that we can drink.

Answer 3

if it's fresh water and can just be consumed like that, there won't be 70% of it left on earth, and you know what's it's gonna be like.

Answer 4

what he said