You-iggy

2CaCr2O7 + 2KHS 💧→ 2CaS↓ + K2CrO4↓ + H2CrO4 + 2CrO3

The reaction of calcium dichromate and potassium hydrogensulfide yields calcium sulfide, potassium chromate, chromic acid, and chromium(VI) oxide (Other reactions are here). This reaction is an acid-base reaction and is classified as follows:

Table of contents
  1. 1Reaction data
  2. 2Thermodynamic changes
  3. 3References
  4. 4Related reactions
  5. 5Related categories

Reaction data

Chemical equation

General equation

Oxidation state of each atom

Reactants

Chemical formulaNameCoefficientTypeType in general
equation
CaCr2O7Calcium dichromate2
Lewis acid
Very soluble in water
KHSPotassium hydrogensulfide2
Lewis base
Soluble in water

Products

Chemical formulaNameCoefficientTypeType in general
equation
CaSCalcium sulfide2
Lewis conjugate
Slightly soluble in water
K2CrO4Potassium chromate1
Lewis conjugate
Insoluble in water
H2CrO4Chromic acid1
Non-redox product
CrO3Chromium(VI) oxide2
Non-redox product

Thermodynamic changes

Thermodynamic data of reactants

Chemical formulaStandard enthalpy
of formation
ΔfH°
kJ · mol−1
Standard Gibbs
energy of
formation
ΔfG°
kJ · mol−1
Standard
molar entropy
S°
J · K−1 · mol−1
Standard molar
heat capacity at
constant pressure
Cp°
J · K−1 · mol−1
CaCr2O7
KHS (cr)-265.10[1]75.31[1]
KHS (ai)-269.9[1]-271.19[1]165.3[1]
KHS (cr)
0.25 hydrate
-337.2[1]
* (cr):Crystalline solid, (ai):Ionized aqueous solution

Thermodynamic data of products

Chemical formulaStandard enthalpy
of formation
ΔfH°
kJ · mol−1
Standard Gibbs
energy of
formation
ΔfG°
kJ · mol−1
Standard
molar entropy
S°
J · K−1 · mol−1
Standard molar
heat capacity at
constant pressure
Cp°
J · K−1 · mol−1
CaS (cr)-482.4[1]-477.4[1]56.5[1]47.40[1]
CaS (g)
K2CrO4 (cr)-1403.7[1]-1295.7[1]200.12[1]145.98[1]
K2CrO4 (ai)-1385.91[1]-1294.30[1]255.2[1]
H2CrO4
CrO3 (cr)-589.5[1]
CrO3 (g)-385.8[1]
* (cr):Crystalline solid, (g):Gas, (ai):Ionized aqueous solution

References

List of references

  1. 1