What is the ph value of tap water to be healthy?

The value of hydrogen ion concentration in water is often expressed by pH value. Simply put, pH value is pH value. A pH above 7.00 is alkaline, and a pH below 7.00 is acidic. The allowable range of standard pH value of tap water quality in this province is 6.5-8.5. In fact, the relationship between pH value and human health is not close, so countries often set this standard according to the pH value of their own water sources. For example, the pH value of tap water in Japan is 5.8-8.5, in Europe it is 6.5-8.5, and in Britain and Germany it is 5.5-9.5. However, the pH value of groundwater sources in some areas of this province is lower than 6.5, but higher than 6.0, which will not affect human health. What is ppm? ppb？ Ppm is a concentration unit, representing one millionth, so it is sometimes used instead of "mg/L"; Ppb is also a unit of concentration, representing one billionth, so sometimes "microgram/liter" is not used; The concentration difference between these two units is 1000 times (1 ppm = 1000 ppb). Sellers of water purifiers often use tap water for electrolysis tests, misleading people into thinking that the water quality of tap water is very poor. What is the principle? Some water purifier salesmen often put a simple electrolytic cell in tap water. After electrification, tap water began to produce brown solids. When the amount of this solid is increasing, the tap water becomes reddish-brown and turbid. Then use this phenomenon to criticize the poor quality of tap water, so as to promote its water purifier. In fact, this is to use the general public's ignorance of electrolysis to achieve its marketing purpose, because tap water often contains some electrolytes (sodium, calcium, magnesium plasma), which is conductive, while water purifiers. After the iron bar of the anode is electrified, due to the action of current, iron ions will be released, which will immediately react with water and become yellow (red) brown iron hydroxide turbidity. If the anode of electrolytic cell is replaced by aluminum rod, aluminum ions will be released, which will react with water and become milky white aluminum hydroxide turbidity. Therefore, the turbidity caused by electrolysis does not come from the quality of tap water, but from the materials used in the anode of electrolytic cell. Another proof method is to add salt to the water produced by the water purifier and electrolyze it in the same way, and the electrolysis phenomenon will be the same as that of tap water users; Because this false electrolysis experiment misled people and hurt the company's image, tap water practitioners should clarify it.