Ca(HSO4)2 + 2KSCN 💧→ CaSO4↓ + 2HSCN + K2SO4
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The reaction of calcium hydrogensulfate and potassium thiocyanate yields calcium sulfate, thiocyanic acid, and potassium sulfate (Other reactions are here). This reaction is an acid-base reaction and is classified as follows:
Table of contents
Reaction data
Chemical equation
- Reaction of calcium hydrogensulfate and potassium thiocyanate
General equation
- Precipitation reaction
- Miscible with water/Very soluble in water/Soluble in waterLewis acid + Miscible with water/Very soluble in water/Soluble in waterLewis base💧⟶ Insoluble in water/Very slightly soluble in water/Slightly soluble in waterLewis conjugate + Product(Non-redox product)
Oxidation state of each atom
- Reaction of calcium hydrogensulfate and potassium thiocyanate
Reactants
| Chemical formula | Name | Coefficient | Type | Type in general equation |
|---|---|---|---|---|
| Ca(HSO4)2 | Calcium hydrogensulfate | 1 | Lewis acid | Soluble in water |
| KSCN | Potassium thiocyanate | 2 | Lewis base | Very soluble in water |
Products
| Chemical formula | Name | Coefficient | Type | Type in general equation |
|---|---|---|---|---|
| CaSO4 | Calcium sulfate | 1 | Lewis conjugate | Slightly soluble in water |
| HSCN | Thiocyanic acid | 2 | Non-redox product | – |
| K2SO4 | Potassium sulfate | 1 | Non-redox product | – |
Thermodynamic changes
Thermodynamic data of reactants
| Chemical formula | Standard 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 |
|---|---|---|---|---|
| Ca(HSO4)2 | – | – | – | – |
| KSCN (cr) | -200.16[1] | -178.31[1] | 124.26[1] | 88.53[1] |
| KSCN (ai) | -175.94[1] | -190.56[1] | 246.9[1] | -18.4[1] |
* (cr):Crystalline solid, (ai):Ionized aqueous solution
Thermodynamic data of products
| Chemical formula | Standard 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 |
|---|---|---|---|---|
| CaSO4 (cr) insoluble, anhydrite | -1434.11[1] | -1321.79[1] | 106.7[1] | 99.66[1] |
| CaSO4 (cr) soluble, α | -1425.24[1] | -1313.42[1] | 108.4[1] | 100.21[1] |
| CaSO4 (cr) soluble, β | -1420.80[1] | -1308.98[1] | 108.4[1] | 99.04[1] |
| CaSO4 (ai) | -1452.10[1] | -1298.10[1] | -33.1[1] | – |
| CaSO4 (cr) 0.5 hydrate macrocrystalline, α | -1576.74[1] | -1436.74[1] | 130.5[1] | 119.41[1] |
| CaSO4 (cr) 0.5 hydrate microcrystalline, β | -1574.65[1] | -1435.78[1] | 134.3[1] | 124.22[1] |
| CaSO4 (cr) 2 hydrate selenite | -2022.63[1] | -1797.28[1] | 194.1[1] | 186.02[1] |
| HSCN (ai) | 76.44[1] | 92.71[1] | 144.3[1] | -40.2[1] |
| HSCN (ao) | – | 97.56[1] | – | – |
| K2SO4 (cr) | -1437.79[1] | -1321.37[1] | 175.56[1] | 131.46[1] |
| K2SO4 (g) | -1096[1] | -1033[1] | 364[1] | 108.8[1] |
| K2SO4 (ai) | -1414.02[1] | -1311.07[1] | 225.1[1] | -251[1] |
* (cr):Crystalline solid, (ai):Ionized aqueous solution, (ao):Un-ionized aqueous solution, (g):Gas
References
List of references
- 1Janiel J. Reed (1989)The NBS Tables of Chemical Thermodynamic Properties: Selected Values for Inorganic and C1 and C2 Organic Substances in SI UnitsNational Institute of Standards and Technology (NIST)
- ^ ΔfH°, -200.16 kJ · mol−1
- ^ ΔfG°, -178.31 kJ · mol−1
- ^ S°, 124.26 J · K−1 · mol−1
- ^ Cp°, 88.53 J · K−1 · mol−1
- ^ ΔfH°, -175.94 kJ · mol−1
- ^ ΔfG°, -190.56 kJ · mol−1
- ^ S°, 246.9 J · K−1 · mol−1
- ^ Cp°, -18.4 J · K−1 · mol−1
- ^ ΔfH°, -1434.11 kJ · mol−1
- ^ ΔfG°, -1321.79 kJ · mol−1
- ^ S°, 106.7 J · K−1 · mol−1
- ^ Cp°, 99.66 J · K−1 · mol−1
- ^ ΔfH°, -1425.24 kJ · mol−1
- ^ ΔfG°, -1313.42 kJ · mol−1
- ^ S°, 108.4 J · K−1 · mol−1
- ^ Cp°, 100.21 J · K−1 · mol−1
- ^ ΔfH°, -1420.80 kJ · mol−1
- ^ ΔfG°, -1308.98 kJ · mol−1
- ^ S°, 108.4 J · K−1 · mol−1
- ^ Cp°, 99.04 J · K−1 · mol−1
- ^ ΔfH°, -1452.10 kJ · mol−1
- ^ ΔfG°, -1298.10 kJ · mol−1
- ^ S°, -33.1 J · K−1 · mol−1
- ^ ΔfH°, -1576.74 kJ · mol−1
- ^ ΔfG°, -1436.74 kJ · mol−1
- ^ S°, 130.5 J · K−1 · mol−1
- ^ Cp°, 119.41 J · K−1 · mol−1
- ^ ΔfH°, -1574.65 kJ · mol−1
- ^ ΔfG°, -1435.78 kJ · mol−1
- ^ S°, 134.3 J · K−1 · mol−1
- ^ Cp°, 124.22 J · K−1 · mol−1
- ^ ΔfH°, -2022.63 kJ · mol−1
- ^ ΔfG°, -1797.28 kJ · mol−1
- ^ S°, 194.1 J · K−1 · mol−1
- ^ Cp°, 186.02 J · K−1 · mol−1
- ^ ΔfH°, 76.44 kJ · mol−1
- ^ ΔfG°, 92.71 kJ · mol−1
- ^ S°, 144.3 J · K−1 · mol−1
- ^ Cp°, -40.2 J · K−1 · mol−1
- ^ ΔfG°, 97.56 kJ · mol−1
- ^ ΔfH°, -1437.79 kJ · mol−1
- ^ ΔfG°, -1321.37 kJ · mol−1
- ^ S°, 175.56 J · K−1 · mol−1
- ^ Cp°, 131.46 J · K−1 · mol−1
- ^ ΔfH°, -1096. kJ · mol−1
- ^ ΔfG°, -1033. kJ · mol−1
- ^ S°, 364. J · K−1 · mol−1
- ^ Cp°, 108.8 J · K−1 · mol−1
- ^ ΔfH°, -1414.02 kJ · mol−1
- ^ ΔfG°, -1311.07 kJ · mol−1
- ^ S°, 225.1 J · K−1 · mol−1
- ^ Cp°, -251. J · K−1 · mol−1