Sulfuric Acid Uses

Sulfuric acid, chemically written as H₂SO₄, is a viscous and oily liquid chemical. There are many different sulfuric acid uses in the industry as it is one of the least expensive acids in the world. The uses of sulfuric acids vary from fertilizers to car battery and as industrial catalysts.

In US, sulfuric acid is listed among the most essential or precursor chemicals by the Chemical Diversion and Trafficking Act. Thus, sale, transfer, export and import of sulfuric acid in US has to be regulated and monitored under the Drug Enforcement Administration. Let us see some sulfuric acid facts before we move on to the main question, what is sulfuric acid used for in chemistry.

Sulfuric Acid Facts

Sulfuric acid is a strong mineral acid that us soluble in water. Pure and concentrated sulfuric acid is does not occur naturally due to its affinity to water. It is also a part of acid rain that is formed due to atmospheric oxidation of sulfur dioxide in presence of H₂O (water). The term acid rain was coined by Robert Smith, an English chemist.

Sulfuric acid is a diprotic acid that means it can donate 2 protons to a base. It can ionize in water in two steps, that are as follows:

1. H₂SO₄ + H₂O (I) ↔ HSO₄^- (aq) + H₃O⁺ (aq)
2. HSO₄^- (aq) + H₂O (I) ↔ SO₄^-2 (aq) + H₃O⁺ (aq)

Sulfuric acid can completely dissociate in water and K_a approaches infinity. This makes sulfuric acid a strong acid. Sulfuric acid can take part in redox reactions too. Sulfuric acid is a good drying agent that can chemically remove water molecules from a number of substances. For example, C₁₁H₂₂O₁₁ (sucrose molecule) can be completely dehydrated by removal of the eleven molecules of water by sulfuric acid. The end product is black mass of carbon. If one accidentally spills H₂SO₄ on skin, the acid begins to remove the oxygen in skin that leads to acid burns.

German chemist Baron Justus von Liebig, in 1800s, discovered that sulfuric acid could be added to soil to increase the availability of phosphorous to the plants. When one cuts onions, it releases propanethiol S-oxide gas. This gas is light and travels through air to reach our eyes. Here, it reacts with water in the eyes to produce sulfuric acid. This is a caustic acid that causes the burning sensation in our eyes. This makes our eyes blink and produce tears. The tears are body's natural way to flush out the irritant acid. Let us now move on to the uses of sulfuric acid.

What is Sulfuric Acid Used for

There are many sulfuric acid uses in industry. The following are a few uses that will help answer your question.

• Sulfuric acid is used in manufacturing fertilizers like ammonium sulfate, super phosphate of lime, etc.
• It is used in manufacturing of hydrochloric acid, nitric acid, phosphoric acid, ether, plastics, metal sulfates, cellophane, dyes, drugs, perfumes, disinfectants and even glue.
• Sulfuric acid is used to manufacture nitroglycerin acid and tri-nitro-toluene (TNT) in the explosive industry.
• Sulfur and tarry compounds in the gasoline are removed by using sulfuric acid.
• It is used as an electrolyte in lead acid batteries.
• Sulfuric acid uses also includes removal of oxides from iron and steel before electroplating or galvanizing.

Sulfuric acid is not considered to be toxic compound but a corrosive compound. Due to its affinity to water it leads to burns. The aerosols can lead to severe eye irritation, respiratory tract and mucous membrane irritation. I hope this article on uses of sulfur proves to be a useful and informative read for you.