How is h2so4 formed

Sulfuric acid is the largest-volume industrial chemical produced in the world million tons per year. The starting material for sulfuric acid manufacture is clean, dry sulfur dioxide SO2 gas.

This can be obtained by burning molten sulfur, from metallurgical off-gases or by decomposing spent sulfuric acid. Over the last decades the contact process has been used to produce sulfuric acid, replacing the traditional «Lead Chamber» process dating back to the 18th Century.

Dilute sulfuric acid reacts with metals higher than hydrogen in the reactivity series to form sulfate salts and hydrogen gas. Note the metal reactions are different with concentrated sulfuric acid. Iron is cleaned free from rust prior to coating with tin to form tinplate and with zinc to form galvanized iron.

Gypsum is CaSO 4. The laxative ' epsom salt ' is MgSO 4. In , Glauber made sulfuric acid by distilling crystals of this salt. Potassium sulfate is unusual in that it crystallizes without water of crystallization and has the formula K 2 SO 4.

As sulfuric acid is dibasic, diprotic it is capable of forming two salts depending on the amount of alkali present in the reaction mixture;.

In , solid frozen sulfuric acid was discovered on Jupiter's moon, Europa. Scientists have even identified solid sulfuric acid hydrates such as hemitriskaidecahydrate H 2 SO 4. Aromatic sulfonation is when an H is replaced by SO 3 H a sulfonic acid group. In the case of benzene, it needs to be heated with conc. H 2 SO 4 for 8 h to produce benzenesulfonic acid. This reaction is too slow and not to be attempted as benzene is implicated in childhood leukemia. Instead, it's better faster and safer to use toluene methylbenzene , as the methyl CH 3 group is electron releasing and speeds up the reaction.

The procedure is: Add 30 drops of conc. H 2 SO 4 to 12 drops of toluene in a test-tube. Warm until the methylbenzene has dissolved into the acid layer. Pour the mixture into 30 cm 3 of a cold saturated solution of sodium chloride. White crystals of sodium methylbenzene sulfonates are formed.

The methyl group is ortho-para directing. Back to Molecule of the Month page. This reaction is reversible. The conditions needed for it are:. In the final stage, sulfur trioxide reacts with water to make sulfuric acid:. This is not a reversible reaction, just like the first stage — aq means aqueous, or dissolved in water. The direct addition of sulfur trioxide to water is highly exothermic and leads to the formation of clouds of sulfuric acid.