Na3PO4 + 2H3PO4 → 3NaH2PO4
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The reaction of sodium phosphate and phosphoric acid yields sodium dihydrogenphosphate (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 sodium phosphate and phosphoric acid
General equation
Oxidation state of each atom
- Reaction of sodium phosphate and phosphoric acid
Reactants
| Chemical formula | Name | Coefficient | Type | Type in general equation |
|---|---|---|---|---|
| Na3PO4 | Sodium phosphate | 1 | Brønsted base | Salt |
| H3PO4 | Phosphoric acid | 2 | Brønsted acid | Acid |
Products
| Chemical formula | Name | Coefficient | Type | Type in general equation |
|---|---|---|---|---|
| NaH2PO4 | Sodium dihydrogenphosphate | 3 | Conjugate acid base | Acid salt |
Thermodynamic changes
Changes in standard condition
- Reaction of sodium phosphate and phosphoric acid◆
ΔrG −131.3 kJ/mol K 1.01 × 1023 pK −23.00
| 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 | −135.0 | −131.3 | −12.33 | −15.01 |
per 1 mol of | −135.0 | −131.3 | −12.33 | −15.01 |
per 1 mol of | −67.50 | −65.65 | −6.165 | −7.505 |
per 1 mol of | −45.00 | −43.77 | −4.110 | −5.003 |
Changes in aqueous solution (1)
- Reaction of sodium phosphate and phosphoric acid◆
ΔrG −86.9 kJ/mol K 1.68 × 1015 pK −15.22
| 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 | −34.6 | −86.9 | 175.1 | – |
per 1 mol of | −34.6 | −86.9 | 175.1 | – |
per 1 mol of | −17.3 | −43.5 | 87.55 | – |
per 1 mol of | −11.5 | −29.0 | 58.37 | – |
Changes in aqueous solution (2)
- Reaction of sodium phosphate and phosphoric acid◆
ΔrG −334.6 kJ/mol K 4.16 × 1058 pK −58.62
| 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 | −56.5 | −334.6 | 932.1 | – |
per 1 mol of | −56.5 | −334.6 | 932.1 | – |
per 1 mol of | −28.3 | −167.3 | 466.1 | – |
per 1 mol of | −18.8 | −111.5 | 310.7 | – |
Changes in aqueous solution (3)
- Reaction of sodium phosphate and phosphoric acid◆
ΔrG −86.9 kJ/mol K 1.68 × 1015 pK −15.22
| 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 | −34.6 | −86.9 | 175.1 | – |
per 1 mol of | −34.6 | −86.9 | 175.1 | – |
per 1 mol of | −17.3 | −43.5 | 87.55 | – |
per 1 mol of | −11.5 | −29.0 | 58.37 | – |
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 |
|---|---|---|---|---|
| Na3PO4 (cr) | -1917.40[1] | -1788.80[1] | 173.80[1] | 153.47[1] |
| Na3PO4 (ai) | -1997.9[1] | -1804.5[1] | -43.3[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] | – | – | – |
* (cr):Crystalline solid, (ai):Ionized aqueous solution, (l):Liquid, (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 |
|---|---|---|---|---|
| NaH2PO4 (cr) | -1536.8[1] | -1386.1[1] | 127.49[1] | 116.86[1] |
| NaH2PO4 (ai) | -1536.41[1] | -1392.17[1] | 149.4[1] | – |
| NaH2PO4 (cr) 1 hydrate | -1833.0[1] | – | – | – |
| NaH2PO4 (cr) 2 hydrate | -2128.4[1] | – | – | – |
* (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°, -1917.40 kJ · mol−1
- ^ ΔfG°, -1788.80 kJ · mol−1
- ^ S°, 173.80 J · K−1 · mol−1
- ^ Cp°, 153.47 J · K−1 · mol−1
- ^ ΔfH°, -1997.9 kJ · mol−1
- ^ ΔfG°, -1804.5 kJ · mol−1
- ^ S°, -43.3 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°, -1536.8 kJ · mol−1
- ^ ΔfG°, -1386.1 kJ · mol−1
- ^ S°, 127.49 J · K−1 · mol−1
- ^ Cp°, 116.86 J · K−1 · mol−1
- ^ ΔfH°, -1536.41 kJ · mol−1
- ^ ΔfG°, -1392.17 kJ · mol−1
- ^ S°, 149.4 J · K−1 · mol−1
- ^ ΔfH°, -1833.0 kJ · mol−1
- ^ ΔfH°, -2128.4 kJ · mol−1