2KI + CaCr2O7 💧→ K2CrO4↓ + CaI2 + CrO3
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The reaction of potassium iodide and calcium dichromate yields potassium chromate, calcium iodide, and chromium(VI) oxide (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 potassium iodide and calcium dichromate
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 potassium iodide and calcium dichromate
Reactants
| Chemical formula | Name | Coefficient | Type | Type in general equation |
|---|---|---|---|---|
| KI | Potassium iodide | 2 | Lewis acid | Very soluble in water |
| CaCr2O7 | Calcium dichromate | 1 | Lewis base | Very soluble in water |
Products
| Chemical formula | Name | Coefficient | Type | Type in general equation |
|---|---|---|---|---|
| K2CrO4 | Potassium chromate | 1 | Lewis conjugate | Insoluble in water |
| CaI2 | Calcium iodide | 1 | Non-redox product | – |
| CrO3 | Chromium(VI) oxide | 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 |
|---|---|---|---|---|
| KI (cr) | -327.900[1] | -324.892[1] | 106.32[1] | 52.93[1] |
| KI (g) | -125.5[1] | -166.1[1] | 258.3[1] | 37.11[1] |
| KI (ai) | -307.57[1] | -334.85[1] | 213.8[1] | -120.5[1] |
| CaCr2O7 | – | – | – | – |
* (cr):Crystalline solid, (g):Gas, (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 |
|---|---|---|---|---|
| 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] | – |
| CaI2 (cr) | -533.5[1] | -528.9[1] | 142[1] | – |
| CaI2 (g) | -272[1] | – | – | – |
| CaI2 (ai) | -653.21[1] | -656.72[1] | 169.5[1] | – |
| CaI2 (cr) 8 hydrate | -2929.6[1] | – | – | – |
| CrO3 (cr) | -589.5[1] | – | – | – |
| CrO3 (g) | -385.8[1] | – | – | – |
* (cr):Crystalline solid, (ai):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°, -327.900 kJ · mol−1
- ^ ΔfG°, -324.892 kJ · mol−1
- ^ S°, 106.32 J · K−1 · mol−1
- ^ Cp°, 52.93 J · K−1 · mol−1
- ^ ΔfH°, -125.5 kJ · mol−1
- ^ ΔfG°, -166.1 kJ · mol−1
- ^ S°, 258.3 J · K−1 · mol−1
- ^ Cp°, 37.11 J · K−1 · mol−1
- ^ ΔfH°, -307.57 kJ · mol−1
- ^ ΔfG°, -334.85 kJ · mol−1
- ^ S°, 213.8 J · K−1 · mol−1
- ^ Cp°, -120.5 J · K−1 · mol−1
- ^ ΔfH°, -1403.7 kJ · mol−1
- ^ ΔfG°, -1295.7 kJ · mol−1
- ^ S°, 200.12 J · K−1 · mol−1
- ^ Cp°, 145.98 J · K−1 · mol−1
- ^ ΔfH°, -1385.91 kJ · mol−1
- ^ ΔfG°, -1294.30 kJ · mol−1
- ^ S°, 255.2 J · K−1 · mol−1
- ^ ΔfH°, -533.5 kJ · mol−1
- ^ ΔfG°, -528.9 kJ · mol−1
- ^ S°, 142. J · K−1 · mol−1
- ^ ΔfH°, -272. kJ · mol−1
- ^ ΔfH°, -653.21 kJ · mol−1
- ^ ΔfG°, -656.72 kJ · mol−1
- ^ S°, 169.5 J · K−1 · mol−1
- ^ ΔfH°, -2929.6 kJ · mol−1
- ^ ΔfH°, -589.5 kJ · mol−1
- ^ ΔfH°, -385.8 kJ · mol−1