Oleum or fuming sulfuric acid available commercially in concentrations ranging from 20 to 99.9% sulfur trioxide.
A. What is the percent by mass of sulfur trioxide (SO3) if oleum is expressed as 3H2SO4 . 5SO3? Show your solution.
B. Discuss at least three potentially hazardous features associated with concentrated sulfuric acid.© BrainMass Inc. brainmass.com December 20, 2018, 8:58 am ad1c9bdddf
Consider the following information when formulating your answers.
To determine the percent by mass of SO3, you will need the molar mass of H2SO4 as well as SO3.
H2SO4 = 98.078 g/mol
SO3 = 80.063 g/mol
Now, we need to factor in the stoichiometric coefficients for each species in oleum to determine the molar mass of oleum.
Molar mass 3H2SO4 . 5SO3 = (98.078 x 3) + (80.063 x 5)
= 694.549 g/mol
The percent by mass of SO3 can then be calculated:
Percent SO3 = [(80.063 x 5) x 100]/694.549
A complete worked through solution for the percent by mass composition of this oleum related question is provided. Additionally, four hazardous features of concentrated sulfuric acid are detailed. Includes references.