Input interpretation
nitric acid + lead sulfide ⟶ water + nitric oxide + lead(II) sulfate
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, Pb and S: H: | c_1 = 2 c_3 N: | c_1 = c_4 O: | 3 c_1 = c_3 + c_4 + 4 c_5 Pb: | c_2 = c_5 S: | c_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_2 = 1 and solve the system of equations for the remaining coefficients: c_1 = 8/3 c_2 = 1 c_3 = 4/3 c_4 = 8/3 c_5 = 1 Multiply by the least common denominator, 3, to eliminate fractional coefficients: c_1 = 8 c_2 = 3 c_3 = 4 c_4 = 8 c_5 = 3 Substitute the coefficients into the chemical reaction to obtain the balanced equation: Answer: | | 8 + 3 ⟶ 4 + 8 + 3
Structures
+ ⟶ + +
Names
nitric acid + lead sulfide ⟶ water + nitric oxide + lead(II) sulfate
Reaction thermodynamics
Gibbs free energy
| nitric acid | lead sulfide | water | nitric oxide | lead(II) sulfate molecular free energy | -80.7 kJ/mol | -98.7 kJ/mol | -237.1 kJ/mol | 87.6 kJ/mol | -813 kJ/mol total free energy | -645.6 kJ/mol | -296.1 kJ/mol | -948.4 kJ/mol | 700.8 kJ/mol | -2439 kJ/mol | G_initial = -941.7 kJ/mol | | G_final = -2687 kJ/mol | | ΔG_rxn^0 | -2687 kJ/mol - -941.7 kJ/mol = -1745 kJ/mol (exergonic) | | | |
Entropy
| nitric acid | lead sulfide | water | nitric oxide | lead(II) sulfate molecular entropy | 156 J/(mol K) | 91 J/(mol K) | 69.91 J/(mol K) | 211 J/(mol K) | 149 J/(mol K) total entropy | 1248 J/(mol K) | 273 J/(mol K) | 279.6 J/(mol K) | 1688 J/(mol K) | 447 J/(mol K) | S_initial = 1521 J/(mol K) | | S_final = 2415 J/(mol K) | | ΔS_rxn^0 | 2415 J/(mol K) - 1521 J/(mol K) = 893.6 J/(mol K) (endoentropic) | | | |
Chemical names and formulas
| nitric acid | lead sulfide | water | nitric oxide | lead(II) sulfate Hill formula | HNO_3 | PbS | H_2O | NO | O_4PbS name | nitric acid | lead sulfide | water | nitric oxide | lead(II) sulfate