How do you recognize that air is a precious resource

1. People need oxygen in the air to breathe.

2. The air provides atmospheric pressure.

3. The flow of air produces wind, which forms the climate.

It can be explained from the use of air, for example, the oxygen in the air can be supplied to the exhalation to support the burning, and the oxygen can be used in industrial steelmaking and gas welding;

Therefore, it can be said that air is a precious natural resource for human beings.

Therefore, it can be said that air is a precious natural resource for human beings.

The composition of air by volume is approximately: nitrogen 78%, oxygen 21%, noble gases helium, neon, argon, krypton, xenon, radon, etc.), carbon dioxide, other gases and impurities.

The reason why air is a precious resource is because of the "life gas" that is breathed every day, which covers the earth's surface in layers, is transparent, colorless and odorless, and it is mainly composed of nitrogen and oxygen, which has an important impact on human survival and production. In its natural state, air is colorless and odorless.

Oxygen in the air is necessary for all aerobic organisms. All animals need to breathe oxygen, as do the respiration of green plants. In addition, greenery makes use of carbon dioxide from the air.

Carry out photosynthesis.

Air is almost the only carbon dioxide required by all plants**. The composition of the air is relatively fixed. This is very important for the survival of humans and other animals and plants.

However, with the development of modern industry, the harmful gases and soot emitted into the air have changed the composition of the air and caused air pollution. Polluted air can seriously damage human health, affect the growth of crops, and cause damage to natural resources and buildings.

Various components in the air are widely used as raw materials in the production of fertilizers, chemical products, petroleum processing, transportation, etc

Therefore, air is an important resource for human production activities.

For example, the main components in the air.

Nitrogen: an important raw material for the production of nitric acid and fertilizers, and can also be used as a protective gas bulb when welding metal.

Village. Oxygen: diving medical emergency, chemical production, making protective gas, flashing lights, etc.

Oxygen, nitrogen, and noble gases are useful substances that are separated from the air. Nitrogen, for example, is an industrial raw material. Nitrogen is slightly less dense than air and rarely dissolves in water.

At atmospheric pressure, nitrogen becomes a colorless liquid when cooled to -196. Liquid nitrogen is an excellent cryogenic agent used in medical applications to preserve blood and living tissues. Freeze-dried human plasma made by freezing fresh blood with liquid nitrogen can be stored for about 5 years.

In the case of a human organ transplant, the living organs transported are also often stored in liquid nitrogen. Nitrogen can not be used for breathing, in the environment of low oxygen and high nitrogen, pests will suffocate, and the metabolism of plants will slow down, so nitrogen is often used to preserve precious paintings and calligraphy, and store grain and vegetables. At room temperature, nitrogen is chemically inactive and does not react easily with other substances.

Nitrogen is used as a shielding gas for welding metals, and is also used to fill the bulb to slow down the evaporation of tungsten filament and make the bulb durable. When lightning strikes, nitrogen in the air also reacts, and the compounds that produce nitrogen fall to the soil on the ground with rainwater, becoming the nitrogen fertilizer necessary for crop growth. It is estimated that more than 400 million tonnes of nitrogen fertilizer dissolves into the soil each year due to lightning strikes.

Ammonia can be synthesized from nitrogen and hydrogen, which is an important nitrogen fertilizer. Ammonia undergoes a series of reactions to produce important nitrogen-containing compounds such as dyes and explosives. Noble gases are also widely used.

Argon is often used to isolate the air when welding and cutting metals. Argon is also used to fill light bulbs to increase the brightness and longevity of the bulb. Noble gases emit colored light when energized, giving them a special application in electric light sources.

The red light emitted by neon gas when it is energized can penetrate dense fog, so neon lamps can be used as indicator lights in ports and airports. Argon and helium produce light blue or light red light respectively when energized, mixed with helium, neon, argon, and mercury vapor to make colorful neon signs. A high-pressure, long-arc xenon lamp filled with xenon can produce intense light and is called an "artificial sun".

Helium, which is lighter than air and does not burn, has replaced hydrogen in filling airboats and balloons, and can also be used to produce helium-oxygen mixtures for divers to breathe (Figs. 1-15). Helium and neon can also be used to make lasers.

Refers to the use of air.

Solution: The volume fractions of each component in the air are as follows: nitrogen accounts for about 78%, oxygen accounts for about 21%, noble gases account for carbon dioxide, water vapor and other gases and impurities account for about that; The composition of the air is mainly nitrogen and oxygen, oxygen accounts for about one-fifth, nitrogen accounts for about four-fifths The most abundant gas in the air is nitrogen, not oxygen; Air is mainly composed of oxygen and nitrogen, of which the mass of oxygen accounts for about the volume of air [1 5], not one-fifth of the mass; The chemical properties of nitrogen are not reactive, and the uses of nitrogen are:

Nitrogen fertilizer is manufactured, nitrogen can be used as protective gas when filled into food packaging bags, and liquid nitrogen can be used as refrigerant; In the air quality report, the smaller the number of air quality levels, the better the air quality, not the worse

a. The gas with the most content in the air is nitrogen, not oxygen, so the option is wrong;

b. Air is mainly composed of oxygen and nitrogen, of which the mass of oxygen accounts for about the volume of air [1 5], not one-fifth of the mass, so the option is wrong;

c. The chemical properties of nitrogen are not active, and the use of nitrogen is: to make nitrogen fertilizer, nitrogen can be used as protective gas when filled into food packaging bags, and liquid nitrogen can be used as refrigerant, so the option is correct;

d. In the air quality report, the smaller the number of air quality levels, the better the air quality, not the worse, so the option is wrong;

Therefore, C7, air is a valuable natural resource The following statement about air is correct ( ).

a The most abundant gas in the air is oxygen.

b Air is mainly composed of oxygen and nitrogen, of which the mass of oxygen accounts for about the mass of air quality [1 5].

c The nitrogen separated from the air is chemically inactive and can be used as a protective gas for food preservation.

d The lower the number of air quality levels in the air quality report, the worse the air quality.

Air is a necessary substance for the survival of most living things, and there is no life without air.

The flow of air brings changes in the atmosphere, and wind, rain, thunder and lightning are the most important natural phenomena on the earth.

Air is a vital but unappreciated treasure that we are in every day but ignores its existence, and no one does not rely on it to live, but it is low-key and unobtrusive, which is where its preciousness lies.

Various components in the air are widely used in the production of chemical fertilizers, chemical products, steelmaking, petroleum processing, transportation, electric light sources and other fields, so air is an important resource for human production activities.

For example, the main components in the air.

Nitrogen: an important raw material for the production of nuclear ridge nitric acid and fertilizers, and can also be used as a protective gas bulb when welding metal in food packaging bags.

Oxygen: Diving Medical Emergency, Steelmaking Gas Welding, Chemical Production, Space Infiltration Navigation.

Rare gases: shielding gases, neon lights, flashing lights, laser technology, etc.

Air contains more than 70 percent oxygen, more than 20 percent carbon dioxide, and many noble gases. The important role of air is mainly reflected in its photosynthetic caution. But as an important resource to understand.

In industry, air can be liquefied and separated to extract our useful ingredients, which is less expensive than chemical reactions. After separation, all kinds of gases can be used in a variety of wide uses, in life, we use paint, with air flow can reduce the waiting time of paint, such as selling fish in the vegetable market, is to use the oxygen machine air to stir the water, so that the fish can survive hail silver for a longer time.

1. Oxygen: respiratory, steelmaking, gas welding, aerospace and other mountain bends;

2. Nitrogen: chemical fertilizer, protective gas, medical treatment, etc.;

3. Rare gases: used as protective gases, emitting different colors of light when energized, and used in laser technology.

Right. The air contains N2 and O2.

N2 is an important raw material for the synthesis of ammonia**, and N is an important element in the composition of proteins.

Oxygen is the gas on which the vast majority of life on Earth depends. Fossil fuels on Earth consume large amounts of oxygen for combustion, reducing gas CO generation in metal smelting, and large amounts of oxygen for steelmaking.

Nitrogen and oxygen can be achieved by separating the liquid air method).

Sort of, air is a mixture, depending on which part you are referring to.

The economic value is not high, and the value of the pure matter is higher than the price, but it is for survival.