how do salt come in water
The earth’s crust consists of many minerals and salts. When any water body flows through these regions, it dissolves these salts. These salts and minerals are also present in the rocks. When a river, lake or stream flows through such a regions, it erodes the rocks and thus dissolves these minerals and salts. These rocks are also eroded by the action of heat, sunlight and rain. This the eroded material is thus washed away by rain water and is deposited river beds. The river when flows through the river beds dissolves these salts.