why ocean water is not drinkable?
550937
Seawater can be turned into drinkable (potable) water by one of a number of desalination processes. Otherwise, it should not be drunk because of its high dissolved mineral content. In the long run, more water must be expended to eliminate these minerals (through excretion in urine) than is gained from drinking the seawater itself.
495612
Sea water is salty because it has dissolved salty solids. These have come from active volcanoes on the floors of the oceans.
782152
Through evaporation, the water evaporates into the air and leaves the salt behind.\n\nWhen the water in the air condenses and comes back to earth as rain or snow or dew, it is again fresh water until it flows into a body of saltwater where it again mixes with the salt.\n\nSalt can also be removed through a variety of chemical and/or electrolytic "desalination" processes, but I assume you mean naturally.\n\nThe principal methods of mass conversion of salt water to fresh water (for providing drinking water in a desert environment or onboard a ship at sea) is done through either distillation, in which the salt water is boiled leaving the salt behind and the steam recondensed to form liquid water, or through a process called osmosis where the water flows through a membrane or material that the salt will not pass through.\n\n=== EDIT ===\n\nYes, a bit of research confirms that the principal method of converting saltwater to freshawater onboard a ship is either a flash-type evaporator (primarily used on older ships and nuclear powered ships) or a reverse-osmosis plant (used on more modern ships).  Both types are also used on US Navy bases where freshwater is not readily available.\n\nThe evaporator basically pre-heats the saltwater to near boiling, and then injects it into a vacuum chamber where it immediately flashes into steam except for a small amount of "brine" left over -- the steam is run through cooled pipes where it condenses into water, and the leftover brine is pumped back overboard.\n\nThe reverse-osmosis uses high pressures to force the water through a membrane which the salt cannot pass through.  Again, the leftover "brine" is pumped back into the ocean since it is just seawater with some of the water removed.
58936
All water, even rain water, contains dissolved chemicals which scientists call "salts." But not all water tastes salty. Water is fresh or salty according to individual judgment, and in making this decision man is more convinced by his sense of taste than by a laboratory test. It is one's taste buds that accept one water and reject another.\nA simple experiment illustrates this. Fill three glasses with water from the kitchen faucet. Drink from one and it tastes fresh even though some dissolved salts are naturally present. Add a pinch of table salt to the second, and the water may taste fresh or slightly salty depending on a personal taste threshold and on the amount of salt held in a "pinch." But add a teaspoon of salt to the third and your taste buds vehemently protest that this water is too salty to drink; this glass of water has about the same salt content as a glass of sea water.\nObviously, the ocean, in contrast to the water we use daily, contains unacceptable amounts of dissolved chemicals; it is too salty for human consumption. \n\nHOW SALTY IS THE OCEAN?...\nHow salty the ocean is, however, defies ordinary comprehension. Some scientists estimate that the oceans contain as much as 50 quadrillion tons (50 million billion tons) of dissolved solids.\n\nIf the salt in the sea could be removed and spread evenly over the Earth's land surface it would form a layer more than 500 feet thick, about the height of a 40-story office building. The saltiness of the ocean is more understandable when compared with the salt content of a fresh-water lake. For example, when 1 cubic foot of sea water evaporates it yields about 2.2 pounds of salt, but 1 cubic foot of fresh water from Lake Michigan contains only one one-hundredth (0.01) of a pound of salt, or about one sixth of an ounce. Thus, sea water is 220 times saltier than the fresh lake water. What arouses the scientist's curiosity is not so much why the ocean is salty, but why it isn't fresh like the rivers and streams that empty into it. Further, what is the origin of the sea and of its "salts"? And how does one explain ocean water's remarkably uniform chemical composition? To these and related questions, scientists seek answers with full awareness that little about the oceans is understood.\n\n\nIllustration: Sources of salts in the ocean.\n\nTHE ORIGIN OF THE SEA...\nIn popular language, "ocean" and "sea" are used interchangeably. Today's seas are the North and South Pacific, North and South Atlantic, Indian and Arctic Oceans and the Antarctic waters or seas.\nScientists believe that the seas are as much as 500 million years old because animals that lived then occur as fossils in rocks which once were under ancient seas. There are several theories about the origin of the seas, but no single theory explains all aspects of this puzzle. Many earth scientists agree with the hypothesis that both the atmosphere and the oceans have accumulated gradually through geologic time from some process of "degassing" of the Earth's interior. According to this theory, the ocean had its origin from the prolonged escape of water vapor and other gases from the molten igneous rocks of the Earth to the clouds surrounding the cooling Earth. After the Earth's surface had cooled to a temperature below the boiling point of water, rain began to fall and continued to fall for centuries. As the water drained into the great hollows in the Earth's surface, the primeval ocean came into existence. The forces of gravity prevented the water from leaving the planet.\n\nSOURCES OF THE SALTS...\nSea water has been defined as a weak solution of almost everything. Ocean water is indeed a complex solution of mineral salts and of decayed biologic matter that results from the teeming life in the seas. Most of the ocean's salts were derived from gradual processes such the breaking up of the cooled igneous rocks of the Earth&#39
546808
Saltwater tastes nasty... kinda ermmmm... saltyish. It's also lethal to some aquatic life whilst essential to others.\n\nAlso drinking salwater will dehydrate you whist fresh water hydrates you.
836878
Yes\n\nThe freezing point of seawater depends upon it's salinity,which is the amount of salt that it contains.  Open ocean seawater has a salinity of about 35. Fresh water freezes at 0 degrees Celsius and 35 water freezes at about -2 degrees C. The decrease is linear so that water with a salinity of 17 freezes at about -1 degree C.\n\n[salinity is no longer given units such as parts per thousand]\n\nIn the winter large tracts of polar seawater freeze to a considerable thickness and even around the UK I remember as a boy that the sea froze along some stretches of beach in the hard winter of (I think) 1963.\n\n[incidentally jane_c, Nikke and others below are wrong - the Titanic sank because it struck an iceberg - an iceberg is NOT frozen seawater but a chunk of a glacier - which is frozen snow (i.e. frozen fresh water)]
303761
Did you ever wonder why the oceans are filled with salt water instead of fresh? Just where did the salt come from? And is it the same salt you find on a dining room table? Most of the salt in the oceans came from land. Over millions of years, rain, rivers, and streams have washed over rocks containing the compound sodium chloride (NaCl), and carried it into the sea. You may know sodium chloride by its common name: table salt! Some of the salt in the oceans comes from undersea volcanoes and hydrothermal vents. When water evaporates from the surface of the ocean, the salt is left behind. After millions of years, the oceans have developed a noticeably salty taste.\n\nDifferent bodies of water have different amounts of salt mixed in, or different salinities. Salinity is expressed by the amount of salt found in 1,000 grams of water. Therefore, if we have 1 gram of salt and 1,000 grams of water, the salinity is 1 part per thousand, or 1 ppt.\n\nThe average ocean salinity is 35 ppt. This number varies between about 32 and 37 ppt. Rainfall, evaporation, river runoff, and ice formation cause the variations. For example, the Black Sea is so diluted by river runoff, its average salinity is only 16 ppt.\n\nFreshwater salinity is usually less than 0.5 ppt. Water between 0.5 ppt and 17 ppt is called brackish. Estuaries (where fresh river water meets salty ocean water) are examples of brackish waters.\n\nMost marine creatures keep the salinity inside their bodies at about the same concentration as the water outside their bodies because water likes a balance. If an animal that usually lives in salt water were placed in fresh water, the fresh water would flow into the animal through its skin. If a fresh water animal found itself in the salty ocean, the water inside of it would rush out. The process by which water flows through a semi-permeable membrane (a material that lets only some things pass through it) such as the animal's skin from an area of high concentration (lots of water, little salt) to an area of low concentration (little water, lots of salt) is called osmosis.\n\nThis is also why humans (and nearly all mammals) cannot drink salt water. When you take in those extra salts, your body will need to expel them as quickly as possible. Your kidneys will try to flush the salts out of your body in urine, and in the process pump out more water than you are taking in. Soon you'll be dehydrated and your cells and organs will not be able to function properly.
290700
(m)\n\nEveryone who has been to the beach knows that seawater is salty. Everyone also knows that fresh water in rain, rivers, and even ice is not salty. Why are some of Earth’s waters salty and others not? There are two clues that give us the answer. First, “fresh” water is not entirely free of dissolved salt. Even rainwater has traces of substances dissolved in it that were picked up during passage through the atmosphere. Much of this material that “washes out” of the atmosphere today is pollution, but there are also natural substances present.\n\nAs rainwater passes through soil and percolates through rocks, it dissolves some of the minerals, a process called weathering. This is the water we drink, and of course, we cannot taste the salt because its concentration is too low. Eventually, this water with its small load of dissolved minerals or salts reaches a stream and flows into lakes and the ocean. The annual addition of dissolved salts by rivers is only a tiny fraction of the total salt in the ocean. The dissolved salts carried by all the world’s rivers would equal the salt in the ocean in about 200 to 300 million years.\n\nA second clue to how the sea became salty is the presence of salt lakes such as the Great Salt Lake and the Dead Sea. Both are about 10 times saltier than seawater. Why are these lakes salty while most of the world’s lakes are not? Lakes are temporary storage areas for water. Rivers and streams bring water to the lakes, and other rivers carry water out of lakes. Thus, lakes are really only wide depressions in a river channel that have filled with water. Water flows in one end and out the other. \n\nThe Great Salt Lake, Dead Sea, and other salt lakes have no outlets. All the water that flows into these lakes escapes only by evaporation. When water evaporates, the dissolved salts are left behind. So a few lakes are salty because rivers carried salts to the lakes, the water in the lakes evaporated and the salts were left behind. After years and years of river inflow and evaporation, the salt content of the lake water built up to the present levels. The same process made the seas salty. Rivers carry dissolved salts to the ocean. Water evaporates from the oceans to fall again as rain and to feed the rivers, but the salts remain in the ocean. Because of the huge volume of the oceans, hundreds of millions of years of river input were required for the salt content to build to its present level. \n\nRivers are not the only source of dissolved salts. About twenty years ago, features on the crest of oceanic ridges were discovered that modified our view on how the sea became salty. These features, known as hydrothermal vents, represent places on the ocean floor where sea water that has seeped into the rocks of the oceanic crust, has become hotter, and has dissolved some of the minerals from the crust, now flows back into the ocean. With the hot water comes a large complement of dissolved minerals. Estimates of the amount of hydrothermal fluids now flowing from these vents indicate that the entire volume of the oceans could seep through the oceanic crust in about 10 million years. Thus, this process has a very important effect on salinity. The reactions between seawater and oceanic basalt, the rock of ocean crust, are not one-way, however; some of the dissolved salts react with the rock and are removed from the water.\n\nA final process that provides salts to the oceans is submarine volcanism, the eruption of volcanoes under water. This is similar to the previous process in that seawater is reacting with hot rock and dissolving some of the mineral constituents.\n\nWill the oceans continue to become saltier? Not likely. In fact the sea has had about the same salt content for many hundred of millions if not billions of years. The salt content has reached a steady state. Dissolved salts are being removed from seawater to form new minerals at the bottom of the ocean as fast as rivers and hydrothermal proce
434979
It is possible to enrich tritium-containing water by sub-boiling-point evaporation - heavier water molecules have a slightly lower "steam pressure" (likelihood to evaporate).\n\nIt is not possible (ok, not feasible - the effort is far greater than de-salting sea water) to remove all tritium from drinking water this way. In case of tritium-rich water supply the easiest way to avoid it is using different water for drinking.
91897
Ok, although the oil and dead cells on the surface of your skin are intended to restrict it as much as possible your skin is very slightly permeable to water.  If you were submerged totally in fresh water you would still dehydrate and die if you didn't drink, but maybe at a slightly slower rate than you might do otherwise.  Because of the osmotic potential of salt water you would probably LOOSE (a very small amount of) water from your tissues to the surrounding water!
276701
the ocean is salty as it contains water colected from different sources such as rivers which bring with them different types of mineral salts before they mingle with the ocean.
22021
Considering our water these days you just have to consider two factors (A) its salty (B) its most likely dirty.\n\nEffects of drinking contaminated water:\nhttp://www.walrus.com/~gatherer/interpret.html#health
814698
I suppose if you took a fresh water fish and put him in the ocean, he wouldn't be able to deal with the salinity and would dehydrate - essentially die of thirst!!
376556
Because of the salt. Salt makes living things/people dehydrated. If a thirsty person drank salt water, they would be even more thirsty.
523968
If the Tar Desert is above the level of the water in the Arabian Sea, then it is not feasible. If the level of the Tar Desert is below the Arabian Sea's level, then it is feasible. Actions such as this will be necessary in order to moderate the increasing severity of drought and global warming.\nThe Arabian Sea is of course salty. The resulting lake - if one was created, would be one of increase salty composition such as the Dead Sea. Even so, water purification would be possible if there were water there. Only a future society with the knowledge and computing power to forecast the resulting weather moderation - and finding it acceptable - would be able to achieve such an undertaking.
828590
The major variable regarding ocean salinity is the 'Water Cycle.' Only pure water evaporates from oceans, lakes and seas. Not salt water. So, any body of water tends to get more salty over time. If all the water evaporates, all that is left is salt. That is why Utah has the great salt flats. The huge lake Bonneville evaporated and left behind miles and miles of salt. \n\nBut in the Water Cycle, the water that evaporates does not just stay up in the air. It forms clouds, rain or snow falls to Earth and flows down rivers back into the oceans, seas and lakes. The water that falls from the sky - not counting any pollution! - is pure water. The rivers and glaciers carry this water - with dissolved minerals and salts - back into the sea. \n\nThe concentration of dissolved minerals and salts of the rivers or glaciers is far less than that in the oceans. So near where fresher water is flowing into the oceans the salinity is lower than that out in the parts of the ocean where there is less rainfall.\n\n;-D There is a lot of water on planet Earth, but not much of it is drinkable! Don't waste water!
258479
Water is H2O. Two hydrogen and one oxygen. Water is the universal solvent because it mixes well with most substances. Water is the most common and mysterious substances on earth. Water is suppose to be a gas ,but it's a liquid at room temperature. Water has a negative side (oxygen) and a positive side (hydrogen). This is another reason why water is the universal solvent it can dissolve just about any solute because the H and O are at 102o angel which means it can pick up most solutes. 97% of the earth's water is salt water will only less than 3% is drinkable. 70% of the earth's animals live in salt water. All animals need water.