Input interpretation
hydrogen + manganese dioxide ⟶ water + manganese
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 Set the number of atoms in the reactants equal to the number of atoms in the products for H, Mn and O: H: | 2 c_1 = 2 c_3 Mn: | c_2 = c_4 O: | 2 c_2 = c_3 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 = 2 c_2 = 1 c_3 = 2 c_4 = 1 Substitute the coefficients into the chemical reaction to obtain the balanced equation: Answer: | | 2 + ⟶ 2 +
Structures
+ ⟶ +
Names
hydrogen + manganese dioxide ⟶ water + manganese
Reaction thermodynamics
Enthalpy
| hydrogen | manganese dioxide | water | manganese molecular enthalpy | 0 kJ/mol | -520 kJ/mol | -285.8 kJ/mol | 0 kJ/mol total enthalpy | 0 kJ/mol | -520 kJ/mol | -571.7 kJ/mol | 0 kJ/mol | H_initial = -520 kJ/mol | | H_final = -571.7 kJ/mol | ΔH_rxn^0 | -571.7 kJ/mol - -520 kJ/mol = -51.66 kJ/mol (exothermic) | | |
Entropy
| hydrogen | manganese dioxide | water | manganese molecular entropy | 115 J/(mol K) | 53 J/(mol K) | 69.91 J/(mol K) | 32 J/(mol K) total entropy | 230 J/(mol K) | 53 J/(mol K) | 139.8 J/(mol K) | 32 J/(mol K) | S_initial = 283 J/(mol K) | | S_final = 171.8 J/(mol K) | ΔS_rxn^0 | 171.8 J/(mol K) - 283 J/(mol K) = -111.2 J/(mol K) (exoentropic) | | |
Chemical names and formulas
| hydrogen | manganese dioxide | water | manganese Hill formula | H_2 | MnO_2 | H_2O | Mn name | hydrogen | manganese dioxide | water | manganese IUPAC name | molecular hydrogen | dioxomanganese | water | manganese
Substance properties
| hydrogen | manganese dioxide | water | manganese molar mass | 2.016 g/mol | 86.936 g/mol | 18.015 g/mol | 54.938044 g/mol phase | gas (at STP) | solid (at STP) | liquid (at STP) | solid (at STP) melting point | -259.2 °C | 535 °C | 0 °C | 1244 °C boiling point | -252.8 °C | | 99.9839 °C | 1962 °C density | 8.99×10^-5 g/cm^3 (at 0 °C) | 5.03 g/cm^3 | 1 g/cm^3 | 7.3 g/cm^3 solubility in water | | insoluble | | insoluble surface tension | | | 0.0728 N/m | dynamic viscosity | 8.9×10^-6 Pa s (at 25 °C) | | 8.9×10^-4 Pa s (at 25 °C) | odor | odorless | | odorless |
Units
