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On a laboratory scale, sulfuric acid can be diluted by pouring concentrated acid onto crushed ice made from de-ionized water. The ice melts in an endothermic process while dissolving the acid. The amount of heat needed to melt the ice in this process is greater than the amount of heat evolved by dissolving the acid so the solution remains cold.
Like concentrated sulfuric acid, oleum is such a strong dehydrating agent that if poured onto powdered glucose, or virtually any other sugar, it will draw the hydrogen elements of water out of the sugar in an exothermic reaction, leaving a residue of nearly pure carbon as a solid. This carbon expands outward, hardening as a solid black ...
High-temperature corrosion is a mechanism of corrosion that takes place when gas turbines, diesel engines, furnaces or other machinery come in contact with hot gas containing certain contaminants. Fuel sometimes contains vanadium compounds or sulfates, which can form low melting point compounds during combustion.
The first and faster [citation needed] process is the removal of hydrogen and oxygen as units of water by the concentrated sulfuric acid. This occurs because hydration of concentrated sulfuric acid is strongly thermodynamically favorable, with a standard enthalpy of reaction of −880 kJ/mol.
Corrosion may occur where stale sewage generates hydrogen sulfide gas into an atmosphere containing oxygen gas and high relative humidity. There must be an underlying anaerobic aquatic habitat containing sulfates and an overlying aerobic aquatic habitat separated by a gas phase containing both oxygen and hydrogen sulfide at concentrations in excess of 2 ppm.
“When salt is added to this system, the ions in salt are attracted to the water molecules in [the surface semi-liquid layer],” Viswanathan says. “The ions on the surface of the salt get ...
The wet sulfuric acid process (WSA process) is a gas desulfurization process. After Danish company Haldor Topsoe introduced this technology in 1987, it has been recognized as a process for recovering sulfur from various process gases in the form of commercial quality sulfuric acid (H 2 SO 4) with the simultaneous production of high-pressure steam.
Magnesium has a mild reaction with cold water. The reaction is short-lived because the magnesium hydroxide layer formed on the magnesium is almost insoluble in water and prevents further reaction. Mg(s) + 2H 2 O(l) Mg(OH) 2 (s) + H 2 (g) [11] A metal reacting with cold water will produce a metal hydroxide and hydrogen gas.