0
The atmosphere is nowadays thought to have been created at the time the Earth was being formed, about 4.5 billion years ago (4.5 GaBP). Asteroids struck the growing planet and caused degassing, chiefly steam, but also hydrogen, nitrogen, carbon dioxide and carbon monoxide. It is now believed that much of this primordial atmosphere was removed quite early after the formation of the Earth by the impact of a body about the size of Mars, which incidentally created the Moon. More outgassing resulted from continued impacts, and at the same time the Earth started to cool. Water vapour condensed and the Earth became covered by oceans. Gravity was insufficient to hold the lightweight outgassed hydrogen (H2), so that escaped to outer space. Most of the carbon dioxide combined with calcium and other minerals to form carbonate rock, but there was enough left for a �greenhouse effect�, preventing the oceans from freezing. CO2 concentrations were perhaps 300 times what they are now. The consequence was that the Earth's atmosphere was warmer than today, and no polar ice caps existed prior to about 2.5 GaBP. The early Earth�s atmosphere was not very different from that of Mars or Venus, except that only on Earth water existed in a liquid state. There was an abrupt increase of free oxygen in the atmosphere to 15% of present concentrations at 2 GaBP, as discussed in Chapter 1.
What else can I help you with?
How is a molecule of ozone different from a molecule of atmospheric oxygen?
Ozone is a tri oxygen molecule. While the ozone layer is formed by the collection of large number of ozone molecules.
What atmospheric gas is required by heterotrophs?
Heterotrophs require oxygen as the essential atmospheric gas for cellular respiration, which is the process that generates ATP (energy) for their metabolic activities.
What can live with or without atmospheric oxygen?
Plants and anaerobic bacteria.
Why MgO is not attacked by atmospheric oxygen?
Magnesium oxide (MgO) is not attacked by atmospheric oxygen because MgO has a high heat of formation and a stable lattice structure. This makes it energetically unfavorable for oxygen to react with MgO under normal atmospheric conditions.
Banded iron formations were caused by the production of which atmospheric gas?
Banded iron formations were caused by the production of oxygen gas. The iron in these formations reacted with the oxygen in the ocean, forming insoluble iron oxides that settled to the seafloor. This process played a crucial role in the Great Oxidation Event, increasing atmospheric oxygen levels.
What was primarily responsible for the development of life outside of the oceans?
"An increase in atmospheric oxygen"An increase in atmospheric oxygen
Where does the bulk of atmospheric oxygen originate from?
The bulk of atmospheric oxygen originates from photosynthesis by plants and phytoplankton in the oceans.
Where did most of earths atmospheric oxygen originally come from?
Most of Earth's atmospheric oxygen originally came from photosynthesis by early cyanobacteria and other photosynthetic organisms around 2.5 billion years ago. These organisms converted carbon dioxide and water into oxygen through the process of photosynthesis, gradually increasing oxygen levels in the atmosphere.
How many oxygen atoms are found in atmospheric oxygen found in the troposphere?
In the troposphere, atmospheric oxygen consists of molecules of O2, each containing two oxygen atoms.
Original oxygen level in water?
The original oxygen level in water can vary depending on factors such as temperature, pressure, and presence of organisms. Typically, at room temperature and normal atmospheric pressure, water can hold about 8-10 mg/L of dissolved oxygen.
What is the major atmospheric by product of photosynthesis and where does it come from?
Oxygen which comes from the synthesis of glucose. Oxygen is the by product of 6CO2 + 6H2O to make C6H12O6 releasing three Oxygen (O2) molecules for every molecule of glucose produced.
Which organism is killed by atmospheric o2?
Anaerobic bacteria are organisms that are killed by atmospheric oxygen. They thrive in environments without oxygen, and exposure to oxygen can be lethal for them.
How is a molecule of ozone different from a molecule of atmospheric oxygen?
Ozone is a tri oxygen molecule. While the ozone layer is formed by the collection of large number of ozone molecules.
What atmospheric layer is pollution found?
Atmospheric pollution is found in the troposphere. It is also containing the oxygen.
What process is most responsible for the increase in early Earths atmospheric oxygen levels?
The process most responsible for the increase in early Earth's atmospheric oxygen levels is photosynthesis. This is the process by which plants, algae, and some bacteria convert carbon dioxide and sunlight into oxygen and energy. Over time, the accumulation of oxygen from photosynthesis led to the rise in atmospheric oxygen levels.
What atmospheric gas is required by heterotrophs?
Heterotrophs require oxygen as the essential atmospheric gas for cellular respiration, which is the process that generates ATP (energy) for their metabolic activities.
What is the current level of atmospheric oxygen on earth?
The current level of atmospheric oxygen on Earth is approximately 21%, although this can vary slightly depending on location and other factors.
