Salt/other physicochemical parameter detection

Table salt refers to different sources of sea salt, well salt, mineral salt, lake salt, soil salt, etc. Their main component is sodium chloride, and the national regulations stipulate that the sodium chloride content of well salt and mineral salt should not be less than 95%. Table salt contains impurities such as barium salt, chloride, magnesium, lead, arsenic, zinc, sulfate, etc. We stipulate that the barium content shall not exceed 20mg/kg. Excessive magnesium and calcium content in table salt can make the salt bitter, while high fluoride content can also cause poisoning. In recent years, many experiments have confirmed that there is a certain relationship between salt intake and the incidence rate of hypertension. Excessive salt intake in the diet can cause hypertension. The World Health Organization (WHO) recommends that individuals consume less than 6g of salt per day to prevent coronary heart disease and hypertension. China stipulates that adults can meet their sodium needs by consuming 6g of salt per day. Salt is indispensable in people's daily lives. The total amount of sodium ions in adults is about 60 g, of which 80% is present in extracellular fluid, i.e. in plasma and intercellular fluid. Chloride ions are also mainly present in extracellular fluids. The physiological functions of sodium and chloride ions are mainly as follows: 1. Maintaining the osmotic pressure of extracellular fluid Na+and Cl - are the main ions that maintain the osmotic pressure of extracellular fluid; K+and H2PO4- are the main ions that maintain the osmotic pressure of intracellular fluid. In the total amount of cations in the extracellular fluid, Na+accounts for over 90%, and in the total amount of anions, Cl - accounts for about 70%. Therefore, table salt plays an important role in maintaining osmotic pressure and affecting the movement of water in the human body. 2. Sodium bicarbonate, formed by Na+and HCO3-, participates in the regulation of acid-base balance in the body and has a buffering effect in the blood. There is also a balance between Cl - and HCO3- in plasma and red blood cells. When HCO3 permeates out of red blood cells, the anions in the red blood cells decrease, and Cl - enters the red blood cells to maintain electrical balance. On the contrary, the same holds true. 3. Chloride ions participate in the generation of gastric acid in the body, and gastric juice is strongly acidic with a pH of approximately 0.9-1.5. Its main components include pepsin, hydrochloric acid, and mucus. The parietal cells in the gastric gland can secrete hydrochloric acid. The parietal cells input HCO3- into the blood and secrete H+into gastric juice. At this point, Cl - enters the gastric juice through parietal cells from the blood to maintain electrical balance. Why can such strong hydrochloric acid not corrode the gastric wall in the stomach? Because there is a type of mucous cell in the gastric gland, the secreted mucus forms a mucus layer about 1mm to 1.5mm thick on the surface of the gastric mucosa, which is often referred to as the barrier of the gastric mucosa. Under the invasion of acid, the gastric mucosa is not digested by digestive enzymes and forms ulcers. But drinking alcohol can weaken the barrier effect of the gastric mucosa, often increasing the likelihood of causing gastric ulcers