I wonder why the sea is salty

I wonder why/ how the sea is salty.

Salt in the ocean comes from rocks on land. The rain that falls on land contains some dissolved carbon dioxide from the surrounding air. This causes the rain to be slightly acidic due to carbonic acid. Sodium and chloride are salty. As the rain slowly dissolves the rocks,  This process creates ions. These ions are carried away in water flow to oceans, Salt lakes etc making them salty. Some estimates say that if we removed all salt from the water on earth and spread it evenly over earths surface of land, it would form a layer more than 500 feet thick. This would be around the height of a 40 story office building.