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HNO3 + HBr = H2O + NO + Br2

Input interpretation

nitric acid + hydrogen bromide ⟶ water + nitric oxide + bromine
nitric acid + hydrogen bromide ⟶ water + nitric oxide + bromine

Balanced equation

Balance the chemical equation algebraically:  + ⟶ + +  Add stoichiometric coefficients, c_i, to the reactants and products: c_1 + c_2 ⟶ c_3 + c_4 + c_5  Set the number of atoms in the reactants equal to the number of atoms in the products for H, N, O and Br: H: | c_1 + c_2 = 2 c_3 N: | c_1 = c_4 O: | 3 c_1 = c_3 + c_4 Br: | c_2 = 2 c_5 Since the coefficients are relative quantities and underdetermined, choose a coefficient to set arbitrarily. To keep the coefficients small, the arbitrary value is ordinarily one. For instance, set c_1 = 1 and solve the system of equations for the remaining coefficients: c_1 = 1 c_2 = 3 c_3 = 2 c_4 = 1 c_5 = 3/2 Multiply by the least common denominator, 2, to eliminate fractional coefficients: c_1 = 2 c_2 = 6 c_3 = 4 c_4 = 2 c_5 = 3 Substitute the coefficients into the chemical reaction to obtain the balanced equation: Answer: |   | 2 + 6 ⟶ 4 + 2 + 3
Balance the chemical equation algebraically: + ⟶ + + Add stoichiometric coefficients, c_i, to the reactants and products: c_1 + c_2 ⟶ c_3 + c_4 + c_5 Set the number of atoms in the reactants equal to the number of atoms in the products for H, N, O and Br: H: | c_1 + c_2 = 2 c_3 N: | c_1 = c_4 O: | 3 c_1 = c_3 + c_4 Br: | c_2 = 2 c_5 Since the coefficients are relative quantities and underdetermined, choose a coefficient to set arbitrarily. To keep the coefficients small, the arbitrary value is ordinarily one. For instance, set c_1 = 1 and solve the system of equations for the remaining coefficients: c_1 = 1 c_2 = 3 c_3 = 2 c_4 = 1 c_5 = 3/2 Multiply by the least common denominator, 2, to eliminate fractional coefficients: c_1 = 2 c_2 = 6 c_3 = 4 c_4 = 2 c_5 = 3 Substitute the coefficients into the chemical reaction to obtain the balanced equation: Answer: | | 2 + 6 ⟶ 4 + 2 + 3

Structures

 + ⟶ + +
+ ⟶ + +

Names

nitric acid + hydrogen bromide ⟶ water + nitric oxide + bromine
nitric acid + hydrogen bromide ⟶ water + nitric oxide + bromine

Reaction thermodynamics

Gibbs free energy

 | nitric acid | hydrogen bromide | water | nitric oxide | bromine molecular free energy | -80.7 kJ/mol | -53.4 kJ/mol | -237.1 kJ/mol | 87.6 kJ/mol | 0 kJ/mol total free energy | -161.4 kJ/mol | -320.4 kJ/mol | -948.4 kJ/mol | 175.2 kJ/mol | 0 kJ/mol  | G_initial = -481.8 kJ/mol | | G_final = -773.2 kJ/mol | |  ΔG_rxn^0 | -773.2 kJ/mol - -481.8 kJ/mol = -291.4 kJ/mol (exergonic) | | | |
| nitric acid | hydrogen bromide | water | nitric oxide | bromine molecular free energy | -80.7 kJ/mol | -53.4 kJ/mol | -237.1 kJ/mol | 87.6 kJ/mol | 0 kJ/mol total free energy | -161.4 kJ/mol | -320.4 kJ/mol | -948.4 kJ/mol | 175.2 kJ/mol | 0 kJ/mol | G_initial = -481.8 kJ/mol | | G_final = -773.2 kJ/mol | | ΔG_rxn^0 | -773.2 kJ/mol - -481.8 kJ/mol = -291.4 kJ/mol (exergonic) | | | |

Entropy

 | nitric acid | hydrogen bromide | water | nitric oxide | bromine molecular entropy | 156 J/(mol K) | 199 J/(mol K) | 69.91 J/(mol K) | 211 J/(mol K) | 152.2 J/(mol K) total entropy | 312 J/(mol K) | 1194 J/(mol K) | 279.6 J/(mol K) | 422 J/(mol K) | 456.7 J/(mol K)  | S_initial = 1506 J/(mol K) | | S_final = 1158 J/(mol K) | |  ΔS_rxn^0 | 1158 J/(mol K) - 1506 J/(mol K) = -347.7 J/(mol K) (exoentropic) | | | |
| nitric acid | hydrogen bromide | water | nitric oxide | bromine molecular entropy | 156 J/(mol K) | 199 J/(mol K) | 69.91 J/(mol K) | 211 J/(mol K) | 152.2 J/(mol K) total entropy | 312 J/(mol K) | 1194 J/(mol K) | 279.6 J/(mol K) | 422 J/(mol K) | 456.7 J/(mol K) | S_initial = 1506 J/(mol K) | | S_final = 1158 J/(mol K) | | ΔS_rxn^0 | 1158 J/(mol K) - 1506 J/(mol K) = -347.7 J/(mol K) (exoentropic) | | | |

Chemical names and formulas

 | nitric acid | hydrogen bromide | water | nitric oxide | bromine Hill formula | HNO_3 | BrH | H_2O | NO | Br_2 name | nitric acid | hydrogen bromide | water | nitric oxide | bromine IUPAC name | nitric acid | hydrogen bromide | water | nitric oxide | molecular bromine
| nitric acid | hydrogen bromide | water | nitric oxide | bromine Hill formula | HNO_3 | BrH | H_2O | NO | Br_2 name | nitric acid | hydrogen bromide | water | nitric oxide | bromine IUPAC name | nitric acid | hydrogen bromide | water | nitric oxide | molecular bromine