Search results
Results from the WOW.Com Content Network
Sulfuryl chloride is used as a source of Cl 2. Because it is a pourable liquid, it is considered more convenient than Cl 2 to dispense. Sulfuryl chloride is used in the conversion of C−H to C−Cl adjacent to activating substituents such as carbonyls and sulfoxides: [5] [6] RC(O)CH 2 R' + SO 2 Cl 2 → RC(O)CHClR' + HCl + SO 2
For gases, departure from 3 R per mole of atoms is generally due to two factors: (1) failure of the higher quantum-energy-spaced vibration modes in gas molecules to be excited at room temperature, and (2) loss of potential energy degree of freedom for small gas molecules, simply because most of their atoms are not bonded maximally in space to ...
As disulfur dichloride is formed, the contents become a golden yellow liquid: [8] S 8 + 4 Cl 2 → 4 S 2 Cl 2, ΔH = −58.2 kJ/mol. Excess chlorine produces sulfur dichloride, which causes the liquid to become less yellow and more orange-red: S 2 Cl 2 + Cl 2 ⇌ 2 SCl 2, ΔH = −40.6 kJ/mol
The addition of Cl 2 to S 2 Cl 2 has been proposed to proceed via a mixed valence intermediate Cl 3 S−SCl. SCl 2 undergoes even further chlorination to give SCl 4, but this species is unstable at near room temperature. It is likely that several S n Cl 2 exist where n > 2. Disulfur dichloride, S 2 Cl 2, is the most common impurity in SCl 2.
Treatment of sulfur with hydrogen gives hydrogen sulfide.When dissolved in water, hydrogen sulfide is mildly acidic: [5] H 2 S ⇌ HS − + H +. Hydrogen sulfide gas and the hydrosulfide anion are extremely toxic to mammals, due to their inhibition of the oxygen-carrying capacity of hemoglobin and certain cytochromes in a manner analogous to cyanide and azide.
Many gases can be put into a liquid state at normal atmospheric pressure by simple cooling; a few, such as carbon dioxide, require pressurization as well. Liquefaction is used for analyzing the fundamental properties of gas molecules (intermolecular forces), or for the storage of gases, for example: LPG , and in refrigeration and air conditioning .
The gas may then be desorbed when subjected to higher temperatures and either combusted to do work or in the case of hydrogen gas extracted for use in a hydrogen fuel cell. Gas storage in activated carbons is an appealing gas storage method because the gas can be stored in a low pressure, low mass, low volume environment that would be much more ...
A major drawback of using coal as a fuel source is the emission of carbon dioxide and pollutants, including sulfur dioxide, nitrogen oxide, mercury, and particulates. Almost all coal-fired power plants use pulverized coal combustion, which grinds the coal to increase the surface area, burns it to make steam, and runs the steam through a turbine ...