How atomicity of oleium can be calculated?
Answers
There is a simple way to determine the atomicity of any element. It can be determined as a ratio of molecular mass and atomic mass. For example, using the case of oxygen molecule, the molecular mass is 32 (= 2x16), while the atomic mass is 16. If we divide the two, we get atomicity as 2 (=32/16).
Explanation:
Oleum (Latin oleum, meaning oil), or fuming sulfuric acid, is a term referring to solutions of various compositions of sulfur trioxide in sulfuric acid, or sometimes more specifically to disulfuric acid (also known as pyrosulfuric acid). Oleum is identified by the CAS number 8014-95-7 (EC/List number: 616-954-1 ; ECHA InfoCard: 100.116.872).
Oleum fuming in air
Oleums can be described by the formula ySO3.H2O where y is the total molar mass of sulfur trioxide content. The value of y can be varied, to include different oleums. They can also be described by the formula H2SO4.xSO3 where x is now defined as the molar free sulfur trioxide content. Oleum is generally assessed according to the free SO3 content by mass. It can also be expressed as a percentage of sulfuric acid strength; for oleum concentrations, that would be over 100%. For example, 10% oleum can also be expressed as H2SO4.0.13611SO3, 1.0225SO3.H2O or 102.25% sulfuric acid. The conversion between % acid and % oleum is: % acid = 100 + 18/80 × % oleum
A value for x of 1 gives the empirical formula H2S2O7 for disulfuric (pyrosulfuric) acid. Pure disulfuric acid is a solid at room temperature, melting at 36 °C and rarely used either in the laboratory or industrial processes.