2(NH4)3PO4 🔥→ 3N2H4 + 2H3PO4 + 3H2↑
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- Decomposition of ammonium phosphate
Decomposition of ammonium phosphate yields hydrazine, phosphoric acid, and (Other reactions are here). This reaction is an oxidation-reduction reaction and is classified as follows:
Table of contents
Reaction data
Chemical equation
- Decomposition of ammonium phosphate
General equation
- Thermal decomposition with redox
- Thermally decomposable substanceSelf redox agent🔥⟶ ProductOxidation product + ProductReduction product
- Thermal decomposition of oxoacid salt with redox
- Oxoacid saltSelf redox agent🔥⟶ ProductOxidation product + ProductReduction product
Oxidation state of each atom
- Decomposition of ammonium phosphate
Reactants
| Chemical formula | Name | Coefficient | Type | Type in general equation |
|---|---|---|---|---|
| (NH4)3PO4 | Ammonium phosphate | 2 | Self redox agent | Thermally decomposable Oxoacid salt |
Products
| Chemical formula | Name | Coefficient | Type | Type in general equation |
|---|---|---|---|---|
| N2H4 | Hydrazine | 3 | Oxidized | – |
| H3PO4 | Phosphoric acid | 2 | – | – |
| 3 | Reduced | – |
Thermodynamic changes
Changes in standard condition
- Decomposition of ammonium phosphate
| 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 | 937.7 | – | – | – |
per 1 mol of | 468.9 | – | – | – |
per 1 mol of | 312.6 | – | – | – |
per 1 mol of | 468.9 | – | – | – |
| 312.6 | – | – | – |
Changes in aqueous solution (1)
- Decomposition of ammonium phosphate◆
ΔrG 612.4 kJ/mol K 0.52 × 10−107 pK 107.29
| 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 | 876.1 | 612.4 | 888 | – |
per 1 mol of | 438.1 | 306.2 | 444 | – |
per 1 mol of | 292.0 | 204.1 | 296 | – |
per 1 mol of | 438.1 | 306.2 | 444 | – |
| 292.0 | 204.1 | 296 | – |
Changes in aqueous solution (2)
- Decomposition of ammonium phosphate◆
ΔrG 665.2 kJ/mol K 0.29 × 10−116 pK 116.54
| 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 | 863.5 | 665.2 | 2227 | – |
per 1 mol of | 431.8 | 332.6 | 1114 | – |
per 1 mol of | 287.8 | 221.7 | 742.3 | – |
per 1 mol of | 431.8 | 332.6 | 1114 | – |
| 287.8 | 221.7 | 742.3 | – |
Changes in aqueous solution (3)
- Decomposition of ammonium phosphate◆
ΔrG 612.4 kJ/mol K 0.52 × 10−107 pK 107.29
| 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 | 876.1 | 612.4 | 888 | – |
per 1 mol of | 438.1 | 306.2 | 444 | – |
per 1 mol of | 292.0 | 204.1 | 296 | – |
per 1 mol of | 438.1 | 306.2 | 444 | – |
| 292.0 | 204.1 | 296 | – |
Changes in aqueous solution (4)
- Decomposition of ammonium phosphate◆
ΔrG 665.2 kJ/mol K 0.29 × 10−116 pK 116.54
| 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 | 863.5 | 665.2 | 2227 | – |
per 1 mol of | 431.8 | 332.6 | 1114 | – |
per 1 mol of | 287.8 | 221.7 | 742.3 | – |
per 1 mol of | 431.8 | 332.6 | 1114 | – |
| 287.8 | 221.7 | 742.3 | – |
Changes in aqueous solution (5)
- Decomposition of ammonium phosphate◆
ΔrG 860.1 kJ/mol K 0.21 × 10−150 pK 150.68
| 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 | 897.9 | 860.1 | 131 | – |
per 1 mol of | 448.9 | 430.1 | 65.5 | – |
per 1 mol of | 299.3 | 286.7 | 43.7 | – |
per 1 mol of | 448.9 | 430.1 | 65.5 | – |
| 299.3 | 286.7 | 43.7 | – |
Changes in aqueous solution (6)
- Decomposition of ammonium phosphate◆
ΔrG 912.9 kJ/mol K 0.12 × 10−159 pK 159.93
| 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 | 885.3 | 912.9 | 1470 | – |
per 1 mol of | 442.6 | 456.4 | 735.0 | – |
per 1 mol of | 295.1 | 304.3 | 490.0 | – |
per 1 mol of | 442.6 | 456.4 | 735.0 | – |
| 295.1 | 304.3 | 490.0 | – |
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 |
|---|---|---|---|---|
| (NH4)3PO4 (cr) | -1671.9[1] | – | – | – |
| (NH4)3PO4 (ai) | -1674.9[1] | -1256.6[1] | 117[1] | – |
| (NH4)3PO4 (cr) 3 hydrate | -2555.6[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 |
|---|---|---|---|---|
| N2H4 (l) | 50.63[1] | 149.34[1] | 121.21[1] | 98.87[1] |
| N2H4 (g) | 95.40[1] | 159.35[1] | 238.47[1] | 49.58[1] |
| N2H4 (ao) | 34.31[1] | 128.1[1] | 138[1] | – |
| H3PO4 (cr) | -1279.0[1] | -1119.1[1] | 110.50[1] | 106.06[1] |
| H3PO4 (l) | -1266.9[1] | – | – | – |
| H3PO4 (ai) | -1277.4[1] | -1018.7[1] | -220.3[1] | – |
| H3PO4 (ao) | -1288.34[1] | -1142.54[1] | 158.2[1] | – |
| H3PO4 (cr) 0.5 hydrate | -1431.3[1] | -1242.1[1] | 129.16[1] | 126.02[1] |
| H3PO4 (cr) 1 hydrate | -1568.83[1] | – | – | – |
| (g) | 0[1] | 0[1] | 130.684[1] | 28.824[1] |
| (ao) | -4.2[1] | 17.6[1] | 577[1] | – |
* (l):Liquid, (g):Gas, (ao):Un-ionized aqueous solution, (cr):Crystalline solid, (ai):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°, -1671.9 kJ · mol−1
- ^ ΔfH°, -1674.9 kJ · mol−1
- ^ ΔfG°, -1256.6 kJ · mol−1
- ^ S°, 117. J · K−1 · mol−1
- ^ ΔfH°, -2555.6 kJ · mol−1
- ^ ΔfH°, 50.63 kJ · mol−1
- ^ ΔfG°, 149.34 kJ · mol−1
- ^ S°, 121.21 J · K−1 · mol−1
- ^ Cp°, 98.87 J · K−1 · mol−1
- ^ ΔfH°, 95.40 kJ · mol−1
- ^ ΔfG°, 159.35 kJ · mol−1
- ^ S°, 238.47 J · K−1 · mol−1
- ^ Cp°, 49.58 J · K−1 · mol−1
- ^ ΔfH°, 34.31 kJ · mol−1
- ^ ΔfG°, 128.1 kJ · mol−1
- ^ S°, 138. J · K−1 · mol−1
- ^ ΔfH°, -1279.0 kJ · mol−1
- ^ ΔfG°, -1119.1 kJ · mol−1
- ^ S°, 110.50 J · K−1 · mol−1
- ^ Cp°, 106.06 J · K−1 · mol−1
- ^ ΔfH°, -1266.9 kJ · mol−1
- ^ ΔfH°, -1277.4 kJ · mol−1
- ^ ΔfG°, -1018.7 kJ · mol−1
- ^ S°, -220.3 J · K−1 · mol−1
- ^ ΔfH°, -1288.34 kJ · mol−1
- ^ ΔfG°, -1142.54 kJ · mol−1
- ^ S°, 158.2 J · K−1 · mol−1
- ^ ΔfH°, -1431.3 kJ · mol−1
- ^ ΔfG°, -1242.1 kJ · mol−1
- ^ S°, 129.16 J · K−1 · mol−1
- ^ Cp°, 126.02 J · K−1 · mol−1
- ^ ΔfH°, -1568.83 kJ · mol−1
- ^ ΔfH°, 0 kJ · mol−1
- ^ ΔfG°, 0 kJ · mol−1
- ^ S°, 130.684 J · K−1 · mol−1
- ^ Cp°, 28.824 J · K−1 · mol−1
- ^ ΔfH°, -4.2 kJ · mol−1
- ^ ΔfG°, 17.6 kJ · mol−1
- ^ S°, 577 J · K−1 · mol−1