Oxygen, as a crucial component of the Earth’s atmosphere, plays an irreplaceable role in maintaining life activities and driving the development of many industries. The density of oxygen, a fundamental property, influences numerous fields, ranging from daily production to cutting – edge scientific research, and contains rich scientific knowledge and huge application potential.

Under standard conditions (0°C, or 32°F, with an atmospheric pressure of 101.325 kPa), the density of oxygen is 1.429 g/L. When converted, it is equivalent to 0.001429 kg/L or 1429 kg/m³. This value is not constant. According to the ideal gas law equation pV = nRT (which can be transformed into the density formula: , where  represents density, P is pressure, M is molar mass, R is the gas constant, and T is temperature), the density of oxygen can change with variations in external conditions.

The density of oxygen is of great significance in various fields. In industrial production, for example, in glass manufacturing, precisely controlling the oxygen density can regulate the combustion process, ensure a stable temperature in the furnace, and thus improve the quality of glass and production efficiency. In scientific research, whether it is an experiment simulating the composition of the Earth’s early atmosphere or a study exploring the atmospheric change laws in high – altitude regions, the oxygen density is an essential key data. In the medical field, for patients with respiratory diseases, doctors need to accurately adjust the oxygen density in the oxygen – supply equipment according to the specific conditions of the patients to ensure that they inhale an appropriate concentration of oxygen and maintain normal physiological functions.

There are strict and standardized procedures for measuring the density of oxygen, which are formulated by international and national relevant institutions. In practical operations, a gas density analyzer is a commonly used measuring tool. It can quickly and accurately measure the oxygen density by using principles such as the oscillating U – tube. With the development of technology, advanced laser technology can now be used to measure the density by analyzing the interaction between light and oxygen molecules, further improving the measurement accuracy and convenience.

The density of oxygen is affected by multiple factors. In terms of temperature, following the principle of thermal expansion and contraction, when the temperature rises, the thermal motion of oxygen molecules intensifies, the distance between molecules increases, and the density decreases. For example, in the hot desert area, the density of oxygen in the air is relatively low under high – temperature conditions. The effect of pressure on the density of oxygen is the opposite. When the pressure increases, the distance between molecules is compressed, and the density rises. For instance, in the high – pressure cylinders of deep – sea diving equipment, the oxygen is compressed, and its density is much higher than that under normal atmospheric pressure. Gas purity also cannot be ignored. The higher the purity of oxygen, the closer its density is to the theoretical value. The presence of other gas impurities will cause the density of the mixed gas to deviate from that of pure oxygen. In addition, humidity dilutes oxygen. In a humid environment, the actual oxygen content in the same volume of air is lower than that in a dry environment.

Oxygen has unique properties. Chemically, it is reactive and highly oxidizing. At room temperature, it can react with many metals and non – metals. For example, aluminum reacts with oxygen in the air to form an aluminum oxide protective film. Under ignition conditions, the reaction is more intense. For example, hydrogen burns in oxygen, releasing a large amount of energy. Physically, under standard conditions, oxygen is colorless, odorless, and tasteless, with a density slightly higher than that of air and is slightly soluble in water. When the temperature drops to – 183°C, it liquefies into a pale – blue liquid. When further cooled to – 218.8°C, it solidifies into a pale – blue snow – like solid. In terms of biological functions, it is an essential substance for the survival of most organisms on Earth. Through respiration, organisms inhale oxygen, which participates in the aerobic respiration process in cells, oxidizes and decomposes organic matter, and releases energy for life activities.

Oxygen has a wide range of applications in the medical field. In addition to providing regular oxygen therapy for patients with respiratory diseases and poor cardiopulmonary function, in emergency rescue scenarios, oxygen is an indispensable “lifesaver”. For example, during the rescue of a patient with cardiac arrest, timely administration of high – flow oxygen with an appropriate density, combined with operations such as cardiopulmonary resuscitation, can increase the patient’s chances of survival. During anesthesia for surgeries, precisely controlling the oxygen density in the gas inhaled by the patient is of great importance. Too low an oxygen density may cause the patient to be hypoxic, affecting the functions of the brain and other vital organs; too high a density may lead to complications such as oxygen toxicity, threatening the patient’s life. Anesthesiologists will carefully adjust the oxygen supply according to factors such as the type of surgery and the patient’s physical condition to ensure the patient’s stable vital signs during anesthesia.

For premature infants and neonates with respiratory distress syndrome, continuous positive airway pressure (CPAP) devices are often used, and the oxygen density is precisely adjusted according to the specific conditions of the infants. This helps to maintain the stability of the alveoli in the infants, ensure sufficient oxygen intake, promote lung development, and improve the success rate of treatment. In rehabilitation physiotherapy, long – term home oxygen therapy is one of the important rehabilitation methods for patients in the recovery period of chronic obstructive pulmonary disease (COPD). By reasonably setting the oxygen density and oxygen – inhalation time of the oxygen – supply equipment, it can improve the patient’s hypoxic state, reduce the burden on the heart and lungs, improve the quality of life, and slow down the progression of the disease.

In hyperbaric oxygen therapy, patients inhale high – concentration oxygen in an environment with a pressure higher than normal. This therapy can be used to treat a variety of diseases. For example, in carbon monoxide poisoning, hyperbaric oxygen can accelerate the elimination of carbon monoxide from the body and improve tissue hypoxia; for hard – to – heal wounds, hyperbaric oxygen can increase the local oxygen supply to the wound, promote cell metabolism and tissue repair; it can also be used to treat decompression sickness and relieve symptoms such as gas embolism caused by pressure changes.

Oxygen also has extensive applications in many other fields. In the metal processing industry, in welding and cutting operations, the high – temperature flame generated by the combustion of oxygen mixed with combustible gases can melt metals and achieve metal processing. In the chemical industry, when producing nitric acid, oxygen participates in the catalytic oxidation process of ammonia, which is an important link in the preparation of nitric acid. In the environmental protection field, when treating rivers, injecting oxygen into the water can promote the decomposition of organic pollutants in the water by aerobic microorganisms and purify the water. In the aviation field, the combustion process of aircraft engines requires the participation of oxygen to provide power for aircraft flight. In soilless cultivation in agriculture, precisely controlling the dissolved oxygen density in the nutrient solution can promote the growth of plant roots and increase crop yields.

When the temperature of oxygen drops below – 183°C, it becomes liquid oxygen. Liquid oxygen is pale blue and highly oxidizing. It is widely used in the field of superconducting technology. By using the low – temperature environment of liquid oxygen, certain materials can reach the superconducting state, reducing resistance and enabling efficient power transmission. However, storing liquid oxygen is challenging. It requires special low – temperature containers, usually double – walled vacuum – insulated tanks, and is also equipped with pressure – regulating and safety – monitoring devices to prevent the vaporization of liquid oxygen from causing excessive pressure and potential hazards.

There are several methods to obtain oxygen. The cryogenic air separation method separates oxygen from air by taking advantage of the different boiling points of nitrogen and oxygen. Air is compressed, cooled, and liquefied, and then separated through a distillation column. Due to the lower boiling point of nitrogen, it vaporizes first, while oxygen remains at the bottom of the column. This method can produce high – purity liquid oxygen and is suitable for large – scale industrial oxygen production. The pressure swing adsorption (PSA) method allows air to pass through a molecular sieve bed under specific pressure conditions. The molecular sieve adsorbs nitrogen, carbon dioxide, and other impurities more strongly than oxygen, resulting in an oxygen – rich gas stream. PSA systems are often used for medium – scale oxygen generation, featuring a simple setup and quick startup. The membrane separation method involves passing compressed air through a selectively permeable membrane. Oxygen molecules pass through the membrane more quickly than other gases, forming an oxygen – rich side on the other side of the membrane. This method is energy – efficient and suitable for small – scale oxygen generation or applications where high purity is not required.

The storage of oxygen needs to be carried out in a suitable way according to its state. Gaseous oxygen is generally stored in high – strength alloy steel high – pressure cylinders. When storing, it is necessary to avoid direct sunlight and high – temperature environments to prevent the pressure in the cylinders from rising. Liquid oxygen is stored in specially designed cryogenic tanks. These tanks have good heat – insulation performance and are equipped with safety valves, pressure gauges, and other safety devices to ensure storage safety at all times.

Although oxygen is essential for life, improper use can be dangerous. A high – concentration oxygen environment is flammable and can easily cause intense combustion or even explosions in case of an open flame. Therefore, it is strictly prohibited to have open flames in places where oxygen is stored and used. Moreover, long – term breathing of high – concentration oxygen can lead to oxygen toxicity in the human body, damaging organs such as the lungs and the nervous system. Therefore, strict safety procedures must be followed when handling oxygen.

Looking to the future, oxygen has great potential applications in emerging fields. In the new energy field, metal – air batteries use oxygen as the positive – electrode reactant. With advantages such as high energy density and environmental friendliness, they are expected to become a new power source for electric vehicles. In the biotechnology field, precisely regulating the oxygen density in the cell – culture environment can optimize the cell growth and metabolism processes, promoting the development of the biopharmaceutical industry. In ocean development, the research and development of efficient underwater oxygen – supply systems can support deep – sea diving operations and ocean resource exploration, expanding the depth and scope of human exploration of the ocean.

In conclusion, the density of oxygen is related to numerous fields. It plays a key role, from basic life support to cutting – edge scientific and technological exploration. With the continuous progress of science and technology, in – depth research and rational utilization of the density of oxygen will bring more opportunities for the development of human society.