Sulfuric Acid

Sulfuric acid (H₂SO₄) is a clear, colorless, odorless, viscous liquid that is very corrosive. As the largest-volume industrial chemical produced in the world, consumption of sulfuric acid is often used to monitor a country's degree of industrialization. Agricultural fertilizers represent the largest single application for sulfuric acid (65%).  Other uses include production of dyes, alcohols, plastics, rubber, ether, glue, film, explosives, drugs, paints, food containers, wood preservatives, soaps and detergents, pharmaceutical products, petroleum products, pulp and paper. The common lead-acid storage battery is one of the few consumer products that actually contains sulfuric acid is the common lead-acid storage battery.

Discovery
Born in Belgium to a noble family, Johann Van Helmont was first to prepare sulfuric acid by destructive distillation of ferrous sulfate (1600).  Van Helmont was also first to recognize and characterize gases--he coined the word "gas."  In his most famous experiment, Van Helmont's planted a tree in a pot of earth and weighed both earth & tree after five years. The weight of the earth had decreased by a few ounces while the weight of the tree increased by over 100 pounds. Van Helmont concluded that the tree gained its weight from water since nothing else added to the pot!
 
 
 

Preparation
Sulfuric acid is often prepared as a byproduct from mining operations. Many  metal ores are sulfides and smelting operations eliminate sulfur in the form of sulfur dioxide gas. Early in the 20th century, sulfur dioxide just went up the smokestack but today smelters must recover the gas. The sulfur dioxide gas is cleaned and converted into sulfuric acid.
The extremely hot sulfur dioxide gas from the furnace gets sprayed with water, cooled, cleaned, dried, run through a catalytic converter, converted to sulfur trioxide (SO₃), and combined with water to make sulfuric acid:
SO₂   +   (O)      SO₃
SO₃   +   H₂O     H₂SO₄
Although sulfur dioxide is considered a  pollutant, it has widespread industrial uses including preservation of fruits/vegetables and as a bleaching agent for flour.
 
 

^.About 40 million tons of sulfuric acid are produced each year in the United States--nearly 300 pounds for every man, woman, and child in the country. Natural processes, including volcano eruptions, forest fires, and decaying vegetation, produce as much sulfur dioxide each year as industry.
^.Sulfuric acid is used as a drying agent to chemically remove water from many substances. If poured on sugar crystals (C₁₁H₂₂O₁₁), the acid removes eleven molecules of water for every molecule of sucrose. After dehydrating the sugar, all  you have left is a brittle, spongy black mass of carbon! If sulfuric acid gets on your skin, it immediately begins to take water out of the molecules in the skin. This is what causes an acid burn.
^.When concentrated sulfuric acid mixed with water, the energy released can be enough to heat the mixture to boiling. When diluted, always add sulfuric acid slowly to cold water and stir to dissipate the heat.
^.Concentrated sulfuric acid is used to prepare HCl/HF/HI:
H₂SO₄  +  NaCl    HCl  +  NaHSO₄
H₂SO₄  +  CaF ₂  2 HF  +  CaSO₄
H₂SO₄  +  2 NaI  2 HI  +  Na₂SO₄
^.In the 1800s, the German chemist Baron Justus von Liebig discovered that adding sulfuric acid to the soil made more phosphorus in the soil available to the plants.

^.Sulfuric Acid Today is a biannual trade magazine covering uses for sulfuric acid in industry. The magazine features articles  include EPA updates, industry and product news, interviews, and mining updates.
 

^.Sulfur dioxide/sulfur trioxide in the atmosphere released mainly by burning coal with high sulfur content. Acid rain,  term coined by English chemist Robert Smith, attacks marble statues by dissolving calcium carbonate.
CaCO₃  +  H₂O ₄CaSO₄  +  H₂O  +  CO₂

^.Frozen sulfuric acid was discovered (1999) on Jupiter's moon Europa by NASA's Galileo spacecraft. The brightest areas, where the yellow is most intense, represent regions of high levels of frozen sulfuric acid.
 
 
 

^.Cutting an onion arouses the gas (propanethiol S-oxide) contained within the onion. When this upwardly mobile gas encounters water in our eyes, sulfuric acid is produced.  In response to the caustic acid, our eyes automatically blink, and produce tears which irrigate the eye, and flushes out the sulfuric acid.