Carbon disturbances

Key Words carbon, disturbance, grazing, fire, global change, hydrocarbons, land cover, modeling, nitrogen, NOx, savanna, sequestration, soil respiration, succession, tree-grass interactions, vegetation dynamics, woody plant encroachment... 

The CC bond distances in cyclopentadienyl anion, C5H5, are all equal, because the anion is aromatic (see Chapter 12, Problem 10). Electrophiles that interact electrostaticaUy with the anion, such as Na", interact equally with all five carbons, and do not disturb the anion s aromatic character. On the other hand, electrophiles that make covalent bonds, such as H", might interact more strongly with one particular carbon and destroy the aromaticity of the ring. 

Burning fossil fuels can release air pollutants such as carbon dioxide, sulfur oxides, nitrogen oxides, ozone, and particulate matter. Sulfur and nitrogen oxides contribute to acid rain ozone is a component of urban smog, and particulate matter affects respiratory health. In fact, several studies have documented a disturbing correlation between suspended particulate levels and human mortality. It is estimated that air pollution may help cause 500,000 premature deaths and millions of new respiratory illnesses each year. 

Solutions in organic solvents may, with certain reservations, be used directly, provided that the viscosity of the solution is not very different from that of an aqueous solution. The important consideration is that the solvent should not lead to any disturbance of the flame an extreme example of this is carbon tetrachloride, which may extinguish an air-acetylene flame. In many cases, suitable organic solvents [e.g. 4-methylpentan-2-one (methyl isobutyl ketone) and the hydrocarbon mixture sold as white spirit ] give enhanced production of ground-state gaseous atoms and lead to about three times the sensitivity... 

Respiratory acidosis and alkalosis result from primary disturbances in the arterial carbon dioxide (C02) levels. Metabolic compensation of respiratory disturbances is a slow process, often requiring days for the serum HC03 to reach the steady state. 

Carbon sequestration in forest disturbed by human activity is lower than in forests less seized by humans. 

An aqueous solution of aluminium formate was being evaporated over a low flame. When the surface crust was disturbed, an explosion occurred. This seems likely to have been due to thermal decomposition of the solid, liberation of carbon monoxide and ignition of the latter admixed with air. 

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