about what is the average concentration of salts in earth's oceans?
The ocean is about 3% salt. This varies a bit though, depending on where you measure it. Near where rivers reach the ocean, the salt content (salinity) will be lower. In fact, because salt water is more dense than fresh water, the river's water will actually float on top of the ocean water until it is mixed together. It is not so much salt of the Earth as all the salt in the sea. Nasa has created the first ever map ever which shows salinity levels in every ocean on the planet – and it could prove key to understanding everything from global rainfall to ocean currents. For example, there is a very low salt concentration in areas where a large river flows in to the ocean, due to high mixing with freshwater. However, in the open ocean away from land the salt content (or salinity) of the seawater tends to range between 30 and 35 ppt (parts per thousand). The ocean has a lot of salt in it, 3.5% by weight, but that is not just dissolved sodium chloride (Na+, Cl-). The dissolved sodium and chlorine atoms account for about 85% of the salt by weight. The ocean contains calcium, magnesium, sodium and potassium with bicarbonate, sulfate, chlorine and bromine. (If you remove the water, then what is left is, by weight, Cl− 55%, Na+ 30.6%, SO2−, 4 7.7%, Mg2+ 3.7%, Ca2+ 1.2%, K+ 1.1%, Other 0.7%) What do you think makes these differences? b) The salinity of the Mediterranean is about 38 parts per mil. a) The Atlantic Ocean is about 34.90 parts per mil on average. c) The Pacific Ocean is about 34.62 parts per mil on average. Salinity in the ocean is in a steady-state. condition because amount of salt added (input. from sources) equals the amount removed. (output to sinks) Ocean is in approx. chemical equilibrium; proportion and amounts of dissolved solids. remain constant. Known as the “steady state ocean”. Steady State Ocean. 2. 3. Average length of time that an ion or. element remains in solution in the ocean. Ions with long residence times tend to. accumulate in the sea; those with short. Page 1 Objective 3: Analyze the physical, chemical, and biological dynamics of the oceans and the flow of energy through the oceans. Ch 15 Earth’s Oceans. SECTION 15.1 An Overview of Oceans. In your textbook, read about modern oceanography. For each item write the word that meets the description. (5 points) ___________________1. Ocean salinity is measured in grams of salt per kilogram of sea water. The range which is measured is currently only between 32 and 37 parts per thousand, but NASA hopes to get this down to 0.2 parts per thousand, a change of just one millilitre of salt in six litres of water. Science Mission Directorate. Science. Salinity. Although everyone knows that seawater is salty, few know that even small variations in ocean surface salinity (i.e., concentration of dissolved salts) can have dramatic effects on the water cycle and ocean circulation. Throughout Earth's history, certain processes have served to make the ocean salty.
3.5%