GEOLOGY

Detailed explanation-1: -Rocks on land are the major source of salts dissolved in seawater. Rainwater that falls on land is slightly acidic, so it erodes rocks. This releases ions that are carried away to streams and rivers that eventually feed into the ocean.

Detailed explanation-2: -Primary source of dissolved substances in the ocean? Chemical weathering of rocks on the continents is one source of elements found in seawater. How do the dissolved mat rials reach the ocean? The reach the oceans through runoff from rivers and streams at an estimated rate or more than 2.3 billion metric tons per year.

Detailed explanation-3: -Chloride and sodium, the components of table salt (sodium chloride NaCl), make up over 85% of the ions in the ocean, which is why seawater tastes salty (Figure 5.3.

Detailed explanation-4: -The most abundant dissolved ions in seawater are sodium, chloride, magnesium, sulfate and calcium.