How to tell the pH of water by feeling?

To be sure, the water in your house is indeed alkaline. Listen to you, and it is calculated from the water plant. If this value is so, it is about+1.5. It is difficult to judge the pH of water by feeling alone. You can go to the chemical store to buy some pH test paper, which is very cheap. When in use, it is very convenient to tear off a strip and drop a drop of solution, and the pH value of the solution can be known from its color change. According to the measurement accuracy, the pH test paper can be divided into 0.2 grade, 0. 1 grade, 0.0 1 grade or higher. In drinking, it is better to drink weakly alkaline water, and so is washing. Generally tap water contains less chloride ions and sulfate ions, mainly bicarbonate ions. This kind of water is weakly alkaline, not acidic. After heating, calcium and magnesium ions will precipitate and become soft water. Of course, some tap water will also be weakly acidic, but in this case, the content of calcium and magnesium ions will be very low, so it is not hard water. In the definition of hard water and soft water, only the content of minerals contained in water is distinguished. When the content reaches a certain value, it becomes hard water. Less than a certain value is soft water. For the human body. The mineral content of hard water is too high for people to drink directly. Now the pure water on the market is generally more suitable for people to drink directly. But we should pay attention to its production index. Relevant indicators can refer to relevant national standards. Many minerals in the human body are obtained from drinking water, so drinking water should not be too hard or too soft. Too hard or too soft is not necessarily harmful to the human body, but depends on the physical quality of the individual. But for the average person, it is better to be soft. Less minerals can be obtained through food, and more minerals will be difficult to clean up. These influences are accumulated over time, so we should pay attention to forming good habits.

You can use a water purifier if possible.

First, drinking pure water is not safe.

China Green Food Development Center said: "Safety, high quality and nutrition" embodies the quality characteristics of green food. The first characteristic is its safety, that is to say, the food will not cause harm to the body under the condition of reasonable consumption and normal consumption. As we all know, an adult needs to drink about 2000 ml of water every day to keep water balance. If an adult drinks about 2000 ml of pure water every day, will it do harm to his health if he drinks it for a long time? Professor Jin of beijing university of chemical technology Water Resources Research Center said: "Water molecules in pure water are extremely series and linear, and it is not easy to pass through the cell membrane, which will lead to the loss of beneficial life-related elements in the body. Some sensitive people will not quench their thirst more and more. The more they drink, the more they want to drink, which will reduce human immunity and even cause some diseases. " Professor Wang Shiwen, an expert on cardiovascular diseases in China and an academician of China Academy of Sciences, pointed out: "Drinking soft water with less minerals for a long time is one of the causes of atherosclerosis." The Naval Medical Research Institute provided a clinical response: "Zhoushan island soldiers drank rain for half a year and generally felt weak." After testing, rainwater lacks minerals and its water quality is similar to pure water. This is an example of the health hazards caused by reasonable drinking methods and normal drinking. Can it be said that pure water is safe food? Hundreds of millions of adults in China drink tap water, natural water or mineral water in the same amount as pure water every day (about 2000 ml). They haven't heard or seen reports about health hazards for more than ten years or decades. In contrast, it is safe to drink tap water, natural water and mineral water often, but it is not safe to drink pure water often.

Second, pure water has no nutrition.

China Green Food Development Center said: "In addition to safety, high quality and nutrition are also important characteristics of green food, which are reflected in the product standards of green food and require it to have excellent sensory characteristics, quality and nutritional value." In this way, green food not only needs excellent sensory characteristics and quality, but also needs excellent nutritional value. Is the nutritional value of pure water high? The affirmative answer is: no! As we all know, after purified water is treated, trace elements and macro elements necessary for human body in water are removed at the same time. Water is an important way for human body to obtain minerals, and it is also the main source under special conditions. Professor Wang Zhansheng from the Department of Environment of Tsinghua University stressed: "At the very least, the existing diet structure of China residents is relatively simple, and it cannot completely and naturally supplement various elements. Therefore, the nutritional role of drinking water cannot be ignored. " Professor Li Fuxing, a water nutrition expert and chairman of the Health Drinking Water Professional Committee of Chinese Medical Association, said: "It has been proved that there are nearly 10 kinds of trace elements necessary for human body in water. As far as the current dietary structure in China is concerned, many trace elements are difficult to obtain from food, mainly from water. The absorption rate of calcium in water can reach over 90%, while the absorption rate of calcium in food is only 30%. " Professor Zhu Huigang, head of the National Drinking Water Hygiene Group and Shanghai Medical University, stressed: "For drinking water, the purer the better. Inorganic elements in water exist in the form of dissolved ions, which are easily absorbed by human body. Therefore, drinking water is an important way for people to absorb minerals. Pure water contains almost no minerals. Previously, it was mainly used for boilers in thermal power plants, washing in electronics industry, integrated circuit boards and so on. Drinking pure water should be cautious, especially for children, the elderly and pregnant women. " The healthy drinking water proposed by the World Health Organization must meet six conditions, namely, no harmful substances, moderate minerals, moderate hardness, rich oxygen, small water mass and weak alkaline pH value. Pure water basically contains no minerals, its hardness is close to 0, its oxygen content is very low (distilled water is 0), its water cluster is large (> > 100Hz), and its pH value is around 6.0, so it is weakly acidic. The drinking water quality standards in Canada and Russia stipulate that the hardness should not be less than 50mg/L (calculated by CaCO3), and the standard hardness of drinking water quality in Europe and America should be kept above 60. Obviously, pure water does not meet the conditions of healthy water, and it has no nutrition, let alone excellent nutritional value. How can it be called green food?

Humans are not supernatural special creatures. Human health depends on nutrients taken from drinking water or food. These nutrients are composed of many chemical elements. For example, oxygen, hydrogen, nitrogen, calcium, phosphorus, sodium, potassium, etc. They are abundant in human body. These elements not only constitute various cells, tissues and organs of human body, but also have many special biological functions. Some trace elements, such as zinc, selenium and fluorine. It is an indispensable component in vitamin, hormone and enzyme systems and has specific biological functions.

Drinking water is an important way for human body to absorb inorganic elements such as potassium, calcium and magnesium from the natural environment. For example, potassium is the main cation in cells and plays an important role in maintaining the normal structure and function of cells. Potassium deficiency can lead to myocardial necrosis.

In addition to calcium, calcium is also an indispensable element for human body. The main component of bones is calcium, and blood also contains some calcium ions. Without these calcium ions, the skin will be cut open and the blood will not coagulate easily. Calcium can also inhibit the absorption of harmful elements such as lead and cadmium. During the baby's growth and development, the bones keep growing and need enough calcium. When there is too little calcium in the human body, the myocardium is weak and the contraction is incomplete, while the excitability of skeletal muscle is enhanced, causing muscle twitching, rickets and osteomalacia.

According to data reports, there are 1/3 children with zinc deficiency in China. Zinc deficiency in children will cause mental retardation and decline in learning ability. Zinc deficiency in pregnant mothers can lead to fetal congenital malformation. Zinc deficiency will also affect the normal development of human brain, heart, pancreas and thyroid. Foreign studies show that zinc deficiency can cause many diseases, such as dwarfism, diabetes, hypertension, hypoplasia of reproductive organs and secondary sexual characteristics, male infertility and so on. Of course, too much zinc intake also has adverse effects.

Selenium deficiency in human body can cause heart disease, hypertension and Keshan disease. Selenium can also reduce the incidence of gastric cancer, intestinal cancer and liver cancer.

Magnesium is another essential element for human body. Magnesium ion is one of the main cations in human cells, and magnesium is also an important element in many enzyme systems. Magnesium deficiency may cause local necrosis and inflammation of myocardium and skeletal muscle. In areas where magnesium is lacking in drinking water, the incidence of cancer is often higher.

Therefore, drinking pure water often leads to the loss of inorganic elements such as potassium, calcium and magnesium, as well as various trace elements such as zinc, selenium and fluorine. Over time, it will inevitably lead to the imbalance of human nutrition. Especially babies and teenagers, are in the stage of intellectual development. In addition, they are very active and consume a lot of inorganic salts and minerals. Drinking pure water regularly will have a negative impact on their healthy growth.

In low fluorine drinking water areas, dental caries often occur due to insufficient fluorine. The fluoride needed by human body mainly comes from drinking water. When the fluorine content in drinking water is less than 0.5 mg per liter, the prevalence of dental caries is as high as 70% ~ 90%; When the fluorine content in drinking water is 0.5 ~ 1.0 mg/L, the prevalence of dental caries is 40%. When the fluorine content in drinking water is 1.5 mg, the prevalence of dental caries is below 10%.

In short, human beings have basically adapted to their own hydrogeochemical environment. Water is the most active substance in the natural environment. The physical properties and chemical composition of natural water are a comprehensive reflection of climate, topography, hydrology, geology, soil, vegetation and other factors in the environment. Drinking water is an important way for human body to absorb inorganic minerals and trace elements from the natural environment. Really high-quality mineral water is an ideal choice for human drinking water. Drinking pure water, "space water" and distilled water for a long time will cause the loss of useful substances in the body, which is not good for the body. The more pure water you drink, the higher the incidence of dental caries, which just illustrates this problem.

Long-term use of pure water is not good for your health. Although it seems that pure water is very convenient to use, from the process flow of pure water, although it is pure after many times of purification, it also filters out minerals that are beneficial to your body while filtering impurities. In this way, people can't supplement some necessary minerals like drinking tap water when drinking water, and living like this for a long time is not good for their health. So I suggest you still use the most commonly used method-burning tap water to drink. Although it is a little troublesome, the high-temperature sterilized tap water does not contain bacteria, but also retains minerals useful to the human body, which is beneficial to the body.

In life, the simplest and most effective way is to add some white vinegar, which can alleviate the problem.