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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 ...
The lead chamber process for sulfuric acid production was abandoned, partly because it could not produce sulfur trioxide or concentrated sulfuric acid directly due to corrosion of the lead, and absorption of NO 2 gas. Until this process was made obsolete by the contact process, oleum had to be obtained through indirect methods.
Even when made with care, the resulting heat can easily bring the solution temperature above 100 °C. It must be allowed to cool reasonably before it is used. A sudden increase in temperature can also lead to a violent boiling of the extremely acidic solution. Solutions made using hydrogen peroxide at concentrations greater than 50 wt % may ...
Sodium bisulfate, also known as sodium hydrogen sulfate, [a] is the sodium salt of the bisulfate anion, with the molecular formula NaHSO 4.Sodium bisulfate is an acid salt formed by partial neutralization of sulfuric acid by an equivalent of sodium base, typically in the form of either sodium hydroxide (lye) or sodium chloride (table salt).
Copper(II) sulfate is an inorganic compound with the chemical formula Cu SO 4.It forms hydrates CuSO 4 ·nH 2 O, where n can range from 1 to 7. The pentahydrate (n = 5), a bright blue crystal, is the most commonly encountered hydrate of copper(II) sulfate, [10] while its anhydrous form is white. [11]
Sulfur trioxide (made by catalysis from sulfur dioxide) and sulfuric acid are similarly highly acidic and corrosive in the presence of water. Concentrated sulfuric acid is a strong dehydrating agent that can strip available water molecules and water components from sugar and organic tissue. [141]
For example, in ammonium chloride solution, NH + 4 is the main influence for acidic solution. It has greater K a value compared to that of water molecules; K a of NH + 4 is 5.6 × 10 −10, and K w of H 2 O is 1.0 × 10 −14. This ensures its deprotonation when reacting with water, and is responsible for the pH below 7 at room temperature.
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.