Input interpretation
calcium hydroxide ⟶ water + lime
Balanced equation
Balance the chemical equation algebraically: ⟶ + Add stoichiometric coefficients, c_i, to the reactants and products: c_1 ⟶ c_2 + c_3 Set the number of atoms in the reactants equal to the number of atoms in the products for Ca, H and O: Ca: | c_1 = c_3 H: | 2 c_1 = 2 c_2 O: | 2 c_1 = 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_1 = 1 and solve the system of equations for the remaining coefficients: c_1 = 1 c_2 = 1 c_3 = 1 Substitute the coefficients into the chemical reaction to obtain the balanced equation: Answer: | | ⟶ +
Structures
⟶ +
Names
calcium hydroxide ⟶ water + lime
Reaction thermodynamics
Enthalpy
| calcium hydroxide | water | lime molecular enthalpy | -985.2 kJ/mol | -285.8 kJ/mol | -634.9 kJ/mol total enthalpy | -985.2 kJ/mol | -285.8 kJ/mol | -634.9 kJ/mol | H_initial = -985.2 kJ/mol | H_final = -920.7 kJ/mol | ΔH_rxn^0 | -920.7 kJ/mol - -985.2 kJ/mol = 64.47 kJ/mol (endothermic) | |
Gibbs free energy
| calcium hydroxide | water | lime molecular free energy | -897.5 kJ/mol | -237.1 kJ/mol | -603.3 kJ/mol total free energy | -897.5 kJ/mol | -237.1 kJ/mol | -603.3 kJ/mol | G_initial = -897.5 kJ/mol | G_final = -840.4 kJ/mol | ΔG_rxn^0 | -840.4 kJ/mol - -897.5 kJ/mol = 57.1 kJ/mol (endergonic) | |
Entropy
| calcium hydroxide | water | lime molecular entropy | 83 J/(mol K) | 69.91 J/(mol K) | 40 J/(mol K) total entropy | 83 J/(mol K) | 69.91 J/(mol K) | 40 J/(mol K) | S_initial = 83 J/(mol K) | S_final = 109.9 J/(mol K) | ΔS_rxn^0 | 109.9 J/(mol K) - 83 J/(mol K) = 26.91 J/(mol K) (endoentropic) | |
Chemical names and formulas
| calcium hydroxide | water | lime Hill formula | CaH_2O_2 | H_2O | CaO name | calcium hydroxide | water | lime IUPAC name | calcium dihydroxide | water |
Substance properties
| calcium hydroxide | water | lime molar mass | 74.092 g/mol | 18.015 g/mol | 56.077 g/mol phase | solid (at STP) | liquid (at STP) | solid (at STP) melting point | 550 °C | 0 °C | 2580 °C boiling point | | 99.9839 °C | 2850 °C density | 2.24 g/cm^3 | 1 g/cm^3 | 3.3 g/cm^3 solubility in water | slightly soluble | | reacts surface tension | | 0.0728 N/m | dynamic viscosity | | 8.9×10^-4 Pa s (at 25 °C) | odor | odorless | odorless |
Units
