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Guilherme Mazui

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What is the Difference Between SO2 and SO3?

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The main difference between SO2 and SO3 lies in their chemical composition, structure, and properties. Here are the key differences between the two compounds:

  • Chemical Composition: SO2, or sulfur dioxide, is a compound composed of one sulfur atom and two oxygen atoms. In contrast, SO3, or sulfur trioxide, is a compound composed of one sulfur atom and three oxygen atoms.
  • Nature: SO2 is a colorless gas at room temperature, while SO3 is a colorless to white crystalline solid.
  • Molar Mass: The molar mass of SO2 is 64 g/mol, whereas the molar mass of SO3 is 80 g/mol.
  • Oxidation State: The oxidation state of sulfur in SO2 is +4, while in SO3, it is +6.
  • Acidity: SO3 is much more acidic than SO2. SO3 is the anhydride of sulfuric acid, while SO2 is the anhydride of sulfurous acid.
  • Polarity: SO2 is a polar compound due to its geometry (angular) and the presence of a lone electron pair. On the other hand, SO3 is a nonpolar compound due to its geometry (trigonal planar) and the absence of a lone electron pair.

In summary, SO2 and SO3 are both oxides of sulfur, but they differ in their chemical composition, structure, and properties. SO2 is a colorless gas, while SO3 is a colorless to white crystalline solid. The oxidation state of sulfur and their acidity also vary between the two compounds.

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  • What is the Difference Between SO2 and SO3?
  • Comparative Table: SO2 vs SO3

    • Comparative Table: SO2 vs SO3

    Here is a table comparing the differences between SO2 and SO3:

    Property SO2 (Sulfur Dioxide) SO3 (Sulfur Trioxide)
    Molecular Formula SO2 SO3
    Molecular Mass 64 g/mol 80 g/mol
    Melting Point (°C) -75°C 16.8°C
    Boiling Point (°C) -10°C 43.7°C
    Density (g/dm³) 1.250 g/dm³ (0°C, 101.3 kPa) 2.052 g/dm³ (20°C, 101.3 kPa)
    Solubility in Water 80 dm³/dm³ (97.7 ppm)
    Oxidation State of Sulfur +4 +6
    Polarity Polar Nonpolar
    Stability More stable under standard conditions Less stable under standard conditions

    SO2 is a colorless gas at room temperature, while SO3 is a colorless to white crystalline solid. The key difference between the two lies in the number of oxygen atoms and the oxidation state of sulfur in each compound.

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    Guilherme Mazui

    Guilherme Mazui is graduated in journalism from the Federal University of Minas Gerais (UFMG) and a master's degree in Communication from the University of São Paulo (USP). In addition, he has experience in advertising writing and has worked as a content editor in several companies.