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Oxygen began building up in the atmosphere at approximately 1.85 Ga. At current rates of primary production, today's concentration of oxygen could be produced by photosynthetic organisms in 2,000 years. [ 4] In the absence of plants, the rate of oxygen production by photosynthesis was slower in the Precambrian, and the concentrations of O 2 ...
Degassing, also known as degasification, is the removal of dissolved gases from liquids, especially water or aqueous solutions. There are numerous methods for removing gases from liquids. Gases are removed for various reasons. Chemists remove gases from solvents when the compounds they are working on are possibly air- or oxygen-sensitive ( air ...
Stages 4 and 5 (0.85 Ga – present): Other O 2 reservoirs filled; gas accumulates in atmosphere. [ 1] The Great Oxidation Event ( GOE) or Great Oxygenation Event, also called the Oxygen Catastrophe, Oxygen Revolution, Oxygen Crisis or Oxygen Holocaust, [ 2] was a time interval during the Earth 's Paleoproterozoic era when the Earth's ...
Paleoatmosphere. A paleoatmosphere (or palaeoatmosphere) is an atmosphere, particularly that of Earth, at some unspecified time in the geological past. The composition of Earth's paleoatmosphere can be inferred today from the study of the abundance of proxy materials such as iron oxides and charcoal and the fossil data, such as the stomatal ...
For example, when sulfuric acid (H 2 SO 4) flows through steel pipes, the iron in the steel reacts with the acid to form a passivation coating of iron sulfate (FeSO 4) and hydrogen gas (H 2). The iron sulfate coating will protect the steel from further reaction; however, if hydrogen bubbles contact this coating, it will be removed.
Oxygen is continuously replenished in Earth's atmosphere by photosynthesis, which uses the energy of sunlight to produce oxygen from water and carbon dioxide. Oxygen is too chemically reactive to remain a free element in air without being continuously replenished by the photosynthetic action of living organisms.
A black smoker, a type of hydrothermal vent. A tremendous glaciation would curtail photosynthetic life on Earth, thus depleting atmospheric oxygen, and thereby allowing non-oxidized iron-rich rocks to form. Detractors argue that this kind of glaciation would have made life extinct entirely.
The atmosphere of Venus is the very dense layer of gasses surrounding the planet Venus. Venus's atmosphere is composed of 96.5% carbon dioxide and 3.5% nitrogen, with other chemical compounds present only in trace amounts. [ 1] It is much denser and hotter than that of Earth; the temperature at the surface is 740 K (467 °C, 872 °F), and the ...