Question

Кислород , в большом количестве используется для дыхания , горения , окисления . Однако его содержание в воздухе с течением времени мало изменилось . Как вы предполагаете ,почему ?

Answer 1

Потому что те количества кислорода, которые потребляются для дыхания , горения , окисления, восполняются благодаря фотосинтезу, происходящему в клетках растений(из угл.газа и воды в хлоропластах, на свету). выделяется кислород!

Answer 2

Why has the oxygen content in the air changed little over time?

Oxygen is a vital component for various processes such as respiration, combustion, and oxidation. Despite the importance of oxygen in these processes, the overall content of oxygen in the Earth's atmosphere has remained relatively stable over time. There are several factors that contribute to this stability.

1. Biological Processes: One of the main reasons for the consistent oxygen content in the atmosphere is the balance between oxygen production and consumption through biological processes. Plants and algae, through photosynthesis, produce oxygen as a byproduct. This process helps maintain a relatively constant level of oxygen in the atmosphere. On the other hand, oxygen is consumed through respiration by animals and other organisms. The balance between oxygen production and consumption helps regulate the overall oxygen content in the atmosphere.

2. Chemical Reactions: Oxygen is involved in various chemical reactions, including combustion and oxidation. These reactions occur continuously in the environment, but they do not significantly alter the overall oxygen content in the atmosphere. The oxygen used in these reactions is eventually released back into the atmosphere through other processes, ensuring a relatively stable oxygen concentration.

3. Earth's Natural Systems: The Earth has natural systems in place that help maintain the stability of oxygen levels in the atmosphere. For example, the carbon cycle plays a crucial role in regulating oxygen levels. Carbon dioxide, a byproduct of respiration and combustion, is absorbed by plants during photosynthesis. This process releases oxygen back into the atmosphere, ensuring a balance between oxygen production and consumption.

4. Geological Processes: Geological processes, such as weathering and volcanic activity, also contribute to the stability of oxygen levels in the atmosphere. Weathering of rocks and minerals releases oxygen into the atmosphere, while volcanic eruptions release gases, including carbon dioxide, which is then used by plants during photosynthesis. These processes help maintain a relatively constant oxygen content in the atmosphere.

In conclusion, the oxygen content in the atmosphere has changed little over time due to the balance between oxygen production and consumption through biological processes, the involvement of oxygen in various chemical reactions, the Earth's natural systems, and geological processes. These factors work together to ensure a relatively stable oxygen concentration in the air.