4 H2SO4 + 3 Ca → 4 H2O + S + 3 CaSO4

This is an oxidation-reduction (redox) reaction:

SVI + 6 e- → S0 (reduction)

3 Ca0 - 6 e- → 3 CaII (oxidation)

H2SO4 is an oxidizing agent, Ca is a reducing agent.

Reactants:

  • H2SO4 – Sulfuric acid source: wikipedia, accessed: 2019-09-27source: wikidata, accessed: 2019-09-07source: NIOSH NPG, accessed: 2019-09-02
    • Other names: Oil of vitriol source: wikipedia, accessed: 2019-09-27source: wikidata, accessed: 2019-09-07source: ICSC, accessed: 2019-09-04source: NIOSH NPG, accessed: 2019-09-02, Sulfuric acid, concentrated (> 51% and < 100%) source: ICSC, accessed: 2019-09-04, H2SO4 source: wikidata, accessed: 2019-09-07
    • Appearance: Clear, colorless liquid source: wikipedia, accessed: 2019-09-27; Odourless colourless oily hygroscopic liquid source: ICSC, accessed: 2019-09-04; Colorless to dark-brown, oily, odorless liquid. [Note: Pure compound is a solid below 51°F. Often used in an aqueous solution.] source: NIOSH NPG, accessed: 2019-09-02
  • Ca
    • Names: Calcium source: wikidata, accessed: 2019-09-07, Calcium (powder) source: ICSC, accessed: 2019-09-04, Ca source: wikidata, accessed: 2019-09-07
    • Appearance: Silvery-white-to-grey powder source: ICSC, accessed: 2019-09-04

Products:

  • H2O – Water, oxidane source: wikipedia, accessed: 2019-09-27
    • Other names: Water (H2O) source: wikipedia, accessed: 2019-09-27, Hydrogen hydroxide (HH or HOH) source: wikipedia, accessed: 2019-09-27, Hydrogen oxide source: wikipedia, accessed: 2019-09-27
    • Appearance: White crystalline solid, almost colorless liquid with a hint of blue, colorless gas source: wikipedia, accessed: 2019-09-27
  • S
    • Names: Sulfur source: wikidata, accessed: 2019-09-07source: ICSC, accessed: 2019-09-04, S source: wikidata, accessed: 2019-09-07, Sulphur source: wikidata, accessed: 2019-09-07source: ICSC, accessed: 2019-09-04
    • Appearance: Yellow solid in various forms source: ICSC, accessed: 2019-09-04
  • CaSO4
    • Names: Calcium sulfate source: wikipedia, accessed: 2019-09-27source: wikidata, accessed: 2019-09-02source: NIOSH NPG, accessed: 2019-09-02, Plaster of Paris source: wikipedia, accessed: 2019-09-27, Drierite source: wikipedia, accessed: 2019-09-27
    • Appearance: White solid source: wikipedia, accessed: 2019-09-27; White hygroscopic powder or crystalline powder source: ICSC, accessed: 2019-09-04; Odorless, white powder or colorless, crystalline solid. [Note: May have blue, gray, or reddish tinge.] source: NIOSH NPG, accessed: 2019-09-02