2KI + 2AgBr 🔥→ 2KBr + I2 + 2Ag
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- Reaction of potassium iodide and silver(I) bromide
The reaction of potassium iodide and silver(I) bromide yields potassium bromide, , and . This reaction is an oxidation-reduction reaction and is classified as follows:
Table of contents
Reaction data
Chemical equation
- Reaction of potassium iodide and silver(I) bromide
General equation
- Reaction of oxidizable species and reducible species
- Oxidizable speciesReducing agent + Reducible speciesOxidizing agent🔥⟶ ProductOxidation product + ProductReduction product
Oxidation state of each atom
- Reaction of potassium iodide and silver(I) bromide
Reactants
| Chemical formula | Name | Coefficient | Type | Type in general equation |
|---|---|---|---|---|
| KI | Potassium iodide | 2 | Reducing | Oxidizable |
| AgBr | Silver(I) bromide | 2 | Oxidizing | Reducible |
Products
| Chemical formula | Name | Coefficient | Type | Type in general equation |
|---|---|---|---|---|
| KBr | Potassium bromide | 2 | – | – |
| 1 | Oxidized | – | ||
| 2 | Reduced | – |
Thermodynamic changes
Changes in standard condition
- Reaction of potassium iodide and silver(I) bromide◆
ΔrG 82.26 kJ/mol K 0.39 × 10−14 pK 14.41
| Standard enthalpy of reaction ΔrH° kJ · mol−1 | Standard Gibbs energy of reaction ΔrG° kJ · mol−1 | Standard entropy of reaction ΔrS° J · K−1 · mol−1 | Standard heat capacity of reaction at constant pressure ΔrCp° J · K−1 · mol−1 | |
|---|---|---|---|---|
per 1 mol of Equation | 68.94 | 82.26 | −33.8 | −0.88 |
per 1 mol of | 34.47 | 41.13 | −16.9 | −0.440 |
per 1 mol of | 34.47 | 41.13 | −16.9 | −0.440 |
per 1 mol of | 34.47 | 41.13 | −16.9 | −0.440 |
| 68.94 | 82.26 | −33.8 | −0.880 | |
| 34.47 | 41.13 | −16.9 | −0.440 |
Changes in aqueous solution (1)
- Reaction of potassium iodide and silver(I) bromide◆
ΔrG −34.64 kJ/mol K 1.17 × 106 pK −6.07
| Standard enthalpy of reaction ΔrH° kJ · mol−1 | Standard Gibbs energy of reaction ΔrG° kJ · mol−1 | Standard entropy of reaction ΔrS° J · K−1 · mol−1 | Standard heat capacity of reaction at constant pressure ΔrCp° J · K−1 · mol−1 | |
|---|---|---|---|---|
per 1 mol of Equation | −78.1 | −34.64 | −145.9 | – |
per 1 mol of | −39.0 | −17.32 | −72.95 | – |
per 1 mol of | −39.0 | −17.32 | −72.95 | – |
per 1 mol of | −39.0 | −17.32 | −72.95 | – |
| −78.1 | −34.64 | −145.9 | – | |
| −39.0 | −17.32 | −72.95 | – |
Changes in aqueous solution (2)
- Reaction of potassium iodide and silver(I) bromide◆
ΔrG 13.6 kJ/mol K 0.41 × 10−2 pK 2.38
| Standard enthalpy of reaction ΔrH° kJ · mol−1 | Standard Gibbs energy of reaction ΔrG° kJ · mol−1 | Standard entropy of reaction ΔrS° J · K−1 · mol−1 | Standard heat capacity of reaction at constant pressure ΔrCp° J · K−1 · mol−1 | |
|---|---|---|---|---|
per 1 mol of Equation | – | 13.6 | – | – |
per 1 mol of | – | 6.80 | – | – |
per 1 mol of | – | 6.80 | – | – |
per 1 mol of | – | 6.80 | – | – |
| – | 13.6 | – | – | |
| – | 6.80 | – | – |
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] |
| AgBr (cr) | -100.37[1] | -96.90[1] | 107.1[1] | 52.38[1] |
| AgBr (ai) | -15.98[1] | -26.86[1] | 155.2[1] | -120.1[1] |
| AgBr (ao) | – | -51.0[1] | – | – |
* (cr):Crystalline solid, (g):Gas, (ai):Ionized aqueous solution, (ao):Un-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 |
|---|---|---|---|---|
| KBr (cr) | -393.798[1] | -380.66[1] | 95.90[1] | 52.30[1] |
| KBr (g) | -180.08[1] | -212.96[1] | 250.52[1] | 36.920[1] |
| KBr (ai) | -373.92[1] | -387.23[1] | 184.9[1] | -120.1[1] |
| (cr) | 0[1] | 0[1] | 116.135[1] | 54.438[1] |
| (g) | 62.438[1] | 19.327[1] | 260.69[1] | 36.90[1] |
| (ao) | 22.6[1] | 16.40[1] | 137.2[1] | – |
| (cr) | 0[1] | 0[1] | 42.55[1] | 25.351[1] |
| (g) | 284.55[1] | 245.65[1] | 172.997[1] | 20.786[1] |
* (cr):Crystalline solid, (g):Gas, (ai):Ionized aqueous solution, (ao):Un-ionized aqueous solution
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°, -100.37 kJ · mol−1
- ^ ΔfG°, -96.90 kJ · mol−1
- ^ S°, 107.1 J · K−1 · mol−1
- ^ Cp°, 52.38 J · K−1 · mol−1
- ^ ΔfH°, -15.98 kJ · mol−1
- ^ ΔfG°, -26.86 kJ · mol−1
- ^ S°, 155.2 J · K−1 · mol−1
- ^ Cp°, -120.1 J · K−1 · mol−1
- ^ ΔfG°, -51.0 kJ · mol−1
- ^ ΔfH°, -393.798 kJ · mol−1
- ^ ΔfG°, -380.66 kJ · mol−1
- ^ S°, 95.90 J · K−1 · mol−1
- ^ Cp°, 52.30 J · K−1 · mol−1
- ^ ΔfH°, -180.08 kJ · mol−1
- ^ ΔfG°, -212.96 kJ · mol−1
- ^ S°, 250.52 J · K−1 · mol−1
- ^ Cp°, 36.920 J · K−1 · mol−1
- ^ ΔfH°, -373.92 kJ · mol−1
- ^ ΔfG°, -387.23 kJ · mol−1
- ^ S°, 184.9 J · K−1 · mol−1
- ^ Cp°, -120.1 J · K−1 · mol−1
- ^ ΔfH°, 0 kJ · mol−1
- ^ ΔfG°, 0 kJ · mol−1
- ^ S°, 116.135 J · K−1 · mol−1
- ^ Cp°, 54.438 J · K−1 · mol−1
- ^ ΔfH°, 62.438 kJ · mol−1
- ^ ΔfG°, 19.327 kJ · mol−1
- ^ S°, 260.69 J · K−1 · mol−1
- ^ Cp°, 36.90 J · K−1 · mol−1
- ^ ΔfH°, 22.6 kJ · mol−1
- ^ ΔfG°, 16.40 kJ · mol−1
- ^ S°, 137.2 J · K−1 · mol−1
- ^ ΔfH°, 0 kJ · mol−1
- ^ ΔfG°, 0 kJ · mol−1
- ^ S°, 42.55 J · K−1 · mol−1
- ^ Cp°, 25.351 J · K−1 · mol−1
- ^ ΔfH°, 284.55 kJ · mol−1
- ^ ΔfG°, 245.65 kJ · mol−1
- ^ S°, 172.997 J · K−1 · mol−1
- ^ Cp°, 20.786 J · K−1 · mol−1