1 In recent years, the U.S. has seen a number of winter storms that have caused surprisâ¦. 2  The Periodic Table of Elements Life is sustained by a number of chemical elements. 3  They are responsible for the birth of planets and the evolution of cells to complex organisms.
Water distribution on Earth - Distribution of saline and fresh water. 1  The total volume of water on Earth is estimated at 1.386 billion kmÂ³ (333 million cubic miles), with 97.5% being salt water and 2.5% being fresh water. 2  The total volume of water in rivers is estimated at 2,120 kmÂ³ (510 cubic miles), or 2% of the surface fresh water on Earth.
Seawater, or salt water, is water from a sea or ocean. On average, seawater in the world's oceans has a salinity of about 3.5% (35 g/L, or 599 mM), which is a specific gravity of about 1.025.This means that every kilogram (roughly one litre by volume) of seawater has approximately 35 grams (1.2 oz) of dissolved salts (predominantly sodium (Na+) and chloride (Clâ) ions).verage density at the surface is 1.025 g / ml. Seawater is denser than both fresh water and pure water (density 1.0 g/ml at 4 Â°C (39 Â°F)) because the dissolved salts increase the mass by a larger proportion than the volume. The freezing point of seawater decreases as salt concentration increases.