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Why can't you drink seawater when you are killed at sea?
Why can't you drink seawater when you are killed at sea?

Everyone knows that there are many harmful things in seawater. Although seawater is also water, its salt content is too high for human body to accept. According to the proof of scientists, we can know the reason: because in our daily life, we should eat vegetables when we eat, but when we cook, we should put salt. If we put too much salt, people will feel thirsty. People who drink seawater will feel thirsty, heavy and insane. If you drink 100 grams of seawater, your body will excrete one hundred and fifty grams of fresh water, so if you don't drink water, you will be more thirsty. According to the statistics of scientists, people who are killed at sea, those who are thirsty for seawater may live 30% less than those who don't drink seawater, so seawater can't be drunk.

However, if you are stranded on an island, there is no fresh water, only seawater, and you are really thirsty, you can turn seawater into fresh water by distillation. First make a fire, scoop some seawater with an iron bowl (if not, you can use shells), then put the bowl on it with a shelf, then put a tube in the bowl (if not, you can use a hollow stick) (let it out at the other end), and then connect another bowl under the other end to wait for the water to flow out of the tube.

Why does this turn seawater into light cement? Because of evaporation, half of the water vapor is evaporated, but the other half reaches another bowl from the pipe. After a period of time, water vapor becomes water droplets in the pipeline, which is fresh water. How does the salt taste? It turned out that salt turned into gas and floated away. If the lid is covered, all the steam will come out of the bowl and enter the pipe, and there will be more water.

Why can't seawater be drunk? What will happen if you drink a little?

A: The reasons are as follows:

Seawater contains a lot of salt and various elements, many of which are needed by human body. However, the concentration of various substances in seawater is too high, far exceeding the hygienic standard of drinking water. If you drink a lot, some elements will enter the human body in excess, affecting the normal physiological function of the human body and even causing poisoning.

If you drink seawater, you can take a lot of fresh water to remedy it. A large amount of fresh water can dilute the excessive minerals and elements ingested by the human body and excrete them through sweat.

According to statistics, among the people killed at sea, the death rate of people who drink seawater is 12 times higher than that of people who don't drink seawater. Why is this? It turns out that in order to discharge the salt contained in100g of seawater, the human body must discharge about150g of water. Therefore, people who drink seawater not only can't replenish the water needed by the human body, but also dehydrate faster and eventually die.

Seawater can be drunk after desalination. There are dozens of desalination methods, the most important of which are distillation, electrodialysis, freezing and membrane separation. Distillation is the most widely used method recently. This method is to boil water to make seawater produce steam, and then condense the steam into distilled water.

It is best to add a small amount (2%) of clean seawater or an appropriate amount of mineralizer to the fresh water obtained by distillation, so that the water tastes delicious and at the same time, it also supplements the inorganic salts that are lacking in distilled water and necessary for human body.

In special circumstances such as maritime distress and lifesaving, in order to save fresh water, some seawater can be mixed with fresh water for drinking. Someone has done experiments. It is generally harmless for people to drink the mixed water of seawater and fresh water in a short time.

Geek Sirius answers for you.

Why can't seawater be drunk?

Seawater is salty because it contains about 3.5% salt, mostly sodium chloride, and a small amount of magnesium chloride, potassium sulfate and calcium carbonate. It is these salts that make seawater bitter and astringent and difficult to enter. Recently, it has been found that eating too salty vegetables is also the inducing factor of influenza, because eating too much salt will reduce saliva secretion and make the virus have a foothold in the mouth; Second, the high permeability of sodium salt will inhibit the defense ability of oral and throat epithelial cells, making it easy for influenza virus to enter the human body.

There is a French proverb that "beauty is born in the mountains, not in the sea." This means that because women by the sea usually eat more salt, the panels are prone to wrinkles. Women in mountainous areas eat less salt, and the panels are often smooth and delicate.

Why is it easy to get wrinkles when you eat too much salt? Experts on the website of French National Medical College explained that salt exists in human blood and body fluids in the form of sodium ions and chlorine, which plays a very important role in maintaining osmotic pressure, acid-base balance and water balance. If you eat too much salt, sodium ions in your body will increase, leading to dehydration of facial cells, which will lead to aging of the panel, which will increase wrinkles for a long time.

Medical experts remind everyone that the daily intake of salt should not exceed 6 grams. Eating too much salt will not only cause high blood pressure, but also directly affect appearance. If you want a good panel, the more scientific method is to drink plenty of water to help the panel detoxify.

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Medical research has found that excessive daily salt intake can easily lead to cardiovascular diseases, so a low-salt diet is advocated. In addition, eating too much salt can also lead to upper respiratory tract infection. This is because high-salt diet can reduce oral saliva secretion and lysozyme, and the osmosis of high-salt diet weakens the role of upper respiratory tract mucosa in resisting disease invasion, leading to the infection of upper respiratory tract diseases. Eating too salty for a long time will also affect bone growth. Because both sodium and calcium are minerals, sodium will be recovered by the body before calcium when passing through the kidney, so excessive sodium intake will indirectly increase the loss of calcium in urine and affect bone development.

Why can't seawater be drunk?

First of all, you should understand the infiltration phenomenon.

In nature, plants absorb water in the soil through the semi-permeable membrane at the root; Sprinkle salt or strong brine on fresh vegetables, and the water in the vegetables will seep out; In human body, the water exchange between plasma and red blood cells, and between interstitial fluid and cells is osmotic phenomenon.

There is a subtle rule. If two kinds of brine with different concentrations are separated by a semi-permeable membrane, water molecules will always permeate from the light brine side to the strong brine side until the concentrations on both sides are equal.

Secondly, you should know that both tissue fluid and cells of human body contain salt, that is, sodium chloride. Under normal circumstances, intracellular solution and extracellular plasma must maintain a certain concentration.

The salt content in seawater is usually more than three times that of human body fluids, so punishing people to drink seawater will greatly increase the salt content in the human body. In order to achieve the same concentration inside and outside the cell, the water in the cell will seep out, resulting in water shortage in the cell. So seawater can't be drunk directly.

The same situation actually exists in blood transfusion. If the concentration of normal saline is too high, the plasma concentration will increase after blood transfusion, and the water in blood cells will permeate outward, resulting in dehydration of cells. If the normal saline is too dilute, the water in the plasma will penetrate into the blood cells with high concentration. In this way, blood cells will swell or even rupture, leading to hemolysis.

Simply put, seawater contains a lot of elements and the salt concentration is too high. Drinking too much will have adverse effects on the body.

Why do people die of thirst at sea? Why can't seawater be drunk?

When the concentration of seawater is higher than the concentration of body fluids (blood cell lymph), it will absorb water from the human body, that is, the salt content of seawater is too high, so the human body does not need so much salt, so it needs to urinate or sweat to discharge these salts, which requires a lot of water, more than the water contained in seawater! The more you drink, the more thirsty you are!

Why can't seawater be drunk?

The sea water is not exactly the same as the water we usually drink. If we put seawater and fresh water in two pots respectively, and then heat them to evaporate the water, you will find that there are almost no solid substances left in the pot filled with fresh water, while there are white solid substances precipitated in the pot filled with seawater. Why is this happening? It turns out that fresh water is composed of water and trace mineral elements. In the process of heating and evaporation, fresh water is continuously vaporized and finally completely converted into steam to escape. So there is basically no residue in the pot. However, the family members of seawater are very complicated. 1 kg seawater contains about 35 grams of salt and a large number of substances such as calcium sulfate and magnesium sulfate. These substances have a high melting point and are not volatile. In the process of heating seawater, water is continuously converted into steam, and the concentration of seawater is also increasing. After the water is completely evaporated, these substances are deposited in the bottom of the pot in solid form. Because salt is salty, calcium sulfate is astringent and magnesium sulfate is bitter, seawater becomes salty, astringent and bitter, so it can't be drunk directly.

Where do these substances in seawater come from? It turns out that the rivers on land are constantly scouring the soil and rocks on both sides of the river in the process of flowing to the sea. Soluble minerals on the land are dissolved by the current and brought into the sea by the current, so the sea water gradually becomes salty, bitter and astringent.

If you drink seawater, you can take a lot of fresh water to remedy it. A large amount of fresh water can dilute the excessive minerals and elements ingested by the human body and excrete them through sweat.

According to statistics, among the people killed at sea, the death rate of people who drink seawater is 12 times higher than that of people who don't drink seawater. Why is this? It turns out that in order to discharge the salt contained in100g of seawater, the human body must discharge about150g of water. Therefore, people who drink seawater not only can't replenish the water needed by the human body, but also dehydrate faster and eventually die.

Seawater can be drunk after desalination. There are dozens of desalination methods, the most important of which are distillation, electrodialysis, freezing and membrane separation. Distillation is the most widely used method recently. This method is to boil water to make seawater produce steam, and then condense the steam into distilled water.

It is best to add a small amount (2%) of clean seawater or an appropriate amount of mineralizer to the fresh water obtained by distillation, so that the water tastes delicious and at the same time, it also supplements the inorganic salts that are lacking in distilled water and necessary for human body.

In special circumstances such as maritime distress and lifesaving, in order to save fresh water, some seawater can be mixed with fresh water for drinking. Someone has done experiments. It is generally harmless for people to drink the mixed water of seawater and fresh water in a short time.

Why can't seawater be drunk, bathed or washed?

Of course, many minerals, salts, plankton, bacteria and so on in the seawater field can't be drunk, because these things are not to mention the unclean water with such high concentration. Will they get drunk?

As for washing clothes, what do you want your clothes to become hard and dry?

As for taking a bath, if it is not clean after washing, there will be water shortage.

Why can't seawater be drunk?

Water contains a lot of salt and various elements, many of which are needed by human body. However, the concentration of various substances in seawater is too high, far exceeding the hygienic standard of drinking water. If you drink a lot, some elements will enter the human body in excess, affecting the normal physiological function of the human body and even causing poisoning.

If you drink seawater, you can take a lot of fresh water to remedy it. A large amount of fresh water can dilute the excessive minerals and elements ingested by the human body and excrete them through sweat.

According to statistics, among the people killed at sea, the death rate of people who drink seawater is 12 times higher than that of people who don't drink seawater. Why is this? It turns out that in order to discharge the salt contained in100g of seawater, the human body must discharge about150g of water. Therefore, people who drink seawater not only can't replenish the water needed by the human body, but also dehydrate faster and eventually die.

Seawater can be drunk after desalination. There are dozens of desalination methods, the most important of which are distillation, electrodialysis, freezing and membrane separation. Distillation is the most widely used method recently. This method is to boil water to make seawater produce steam, and then condense the steam into distilled water.

It is best to add a small amount (2%) of clean seawater or an appropriate amount of mineralizer to the fresh water obtained by distillation, so that the water tastes delicious and at the same time, it also supplements the inorganic salts that are lacking in distilled water and necessary for human body.

In special circumstances such as maritime distress and lifesaving, in order to save fresh water, some seawater can be mixed with fresh water for drinking. Someone has done experiments. It is generally harmless for people to drink the mixed water of seawater and fresh water in a short time.

Why can't you drink seawater when you are killed at sea?

Everyone knows that there are many harmful things in seawater. Although seawater is also water, its salt content is too high for human body to accept. According to the proof of scientists, we can know the reason: because in our daily life, we should eat vegetables when we eat, but when we cook, we should put salt. If we put too much salt, people will feel thirsty. People who drink seawater will feel thirsty, heavy and insane. If you drink 100 grams of seawater, your body will excrete one hundred and fifty grams of fresh water, so if you don't drink water, you will be more thirsty. According to the statistics of scientists, people who are killed at sea, those who are thirsty for seawater may live 30% less than those who don't drink seawater, so seawater can't be drunk. However, if you are stranded on an island, there is no fresh water, only seawater, and you are really thirsty, you can turn seawater into fresh water by distillation. First make a fire, scoop some seawater with an iron bowl (if not, you can use shells), then put the bowl on it with a shelf, then put a tube in the bowl (if not, you can use a hollow stick) (let it out at the other end), and then connect another bowl under the other end to wait for the water to flow out of the tube.