Input interpretation
AgO silver(II) oxide ⟶ O_2 oxygen + Ag silver
Balanced equation
Balance the chemical equation algebraically: AgO ⟶ O_2 + Ag Add stoichiometric coefficients, c_i, to the reactants and products: c_1 AgO ⟶ c_2 O_2 + c_3 Ag Set the number of atoms in the reactants equal to the number of atoms in the products for Ag and O: Ag: | c_1 = c_3 O: | c_1 = 2 c_2 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 Substitute the coefficients into the chemical reaction to obtain the balanced equation: Answer: | | 2 AgO ⟶ O_2 + 2 Ag
Structures
⟶ +
Names
silver(II) oxide ⟶ oxygen + silver
Reaction thermodynamics
Enthalpy
| silver(II) oxide | oxygen | silver molecular enthalpy | -24.3 kJ/mol | 0 kJ/mol | 0 kJ/mol total enthalpy | -48.6 kJ/mol | 0 kJ/mol | 0 kJ/mol | H_initial = -48.6 kJ/mol | H_final = 0 kJ/mol | ΔH_rxn^0 | 0 kJ/mol - -48.6 kJ/mol = 48.6 kJ/mol (endothermic) | |
Entropy
| silver(II) oxide | oxygen | silver molecular entropy | 117 J/(mol K) | 205 J/(mol K) | 42.6 J/(mol K) total entropy | 234 J/(mol K) | 205 J/(mol K) | 85.2 J/(mol K) | S_initial = 234 J/(mol K) | S_final = 290.2 J/(mol K) | ΔS_rxn^0 | 290.2 J/(mol K) - 234 J/(mol K) = 56.2 J/(mol K) (endoentropic) | |
Equilibrium constant
Construct the equilibrium constant, K, expression for: AgO ⟶ O_2 + Ag Plan: • Balance the chemical equation. • Determine the stoichiometric numbers. • Assemble the activity expression for each chemical species. • Use the activity expressions to build the equilibrium constant expression. Write the balanced chemical equation: 2 AgO ⟶ O_2 + 2 Ag Assign stoichiometric numbers, ν_i, using the stoichiometric coefficients, c_i, from the balanced chemical equation in the following manner: ν_i = -c_i for reactants and ν_i = c_i for products: chemical species | c_i | ν_i AgO | 2 | -2 O_2 | 1 | 1 Ag | 2 | 2 Assemble the activity expressions accounting for the state of matter and ν_i: chemical species | c_i | ν_i | activity expression AgO | 2 | -2 | ([AgO])^(-2) O_2 | 1 | 1 | [O2] Ag | 2 | 2 | ([Ag])^2 The equilibrium constant symbol in the concentration basis is: K_c Mulitply the activity expressions to arrive at the K_c expression: Answer: | | K_c = ([AgO])^(-2) [O2] ([Ag])^2 = ([O2] ([Ag])^2)/([AgO])^2
Rate of reaction
Construct the rate of reaction expression for: AgO ⟶ O_2 + Ag Plan: • Balance the chemical equation. • Determine the stoichiometric numbers. • Assemble the rate term for each chemical species. • Write the rate of reaction expression. Write the balanced chemical equation: 2 AgO ⟶ O_2 + 2 Ag Assign stoichiometric numbers, ν_i, using the stoichiometric coefficients, c_i, from the balanced chemical equation in the following manner: ν_i = -c_i for reactants and ν_i = c_i for products: chemical species | c_i | ν_i AgO | 2 | -2 O_2 | 1 | 1 Ag | 2 | 2 The rate term for each chemical species, B_i, is 1/ν_i(Δ[B_i])/(Δt) where [B_i] is the amount concentration and t is time: chemical species | c_i | ν_i | rate term AgO | 2 | -2 | -1/2 (Δ[AgO])/(Δt) O_2 | 1 | 1 | (Δ[O2])/(Δt) Ag | 2 | 2 | 1/2 (Δ[Ag])/(Δt) (for infinitesimal rate of change, replace Δ with d) Set the rate terms equal to each other to arrive at the rate expression: Answer: | | rate = -1/2 (Δ[AgO])/(Δt) = (Δ[O2])/(Δt) = 1/2 (Δ[Ag])/(Δt) (assuming constant volume and no accumulation of intermediates or side products)
Chemical names and formulas
| silver(II) oxide | oxygen | silver formula | AgO | O_2 | Ag name | silver(II) oxide | oxygen | silver IUPAC name | oxosilver | molecular oxygen | silver
Substance properties
| silver(II) oxide | oxygen | silver molar mass | 123.867 g/mol | 31.998 g/mol | 107.8682 g/mol phase | solid (at STP) | gas (at STP) | solid (at STP) melting point | 100 °C | -218 °C | 960 °C boiling point | | -183 °C | 2212 °C density | 7.44 g/cm^3 | 0.001429 g/cm^3 (at 0 °C) | 10.49 g/cm^3 solubility in water | | | insoluble surface tension | | 0.01347 N/m | dynamic viscosity | | 2.055×10^-5 Pa s (at 25 °C) | odor | | odorless |
Units