BaO2 = O2 + BaO

BaO_2 barium peroxide ⟶ O_2 oxygen + BaO barium oxide

Balance the chemical equation algebraically: BaO_2 ⟶ O_2 + BaO Add stoichiometric coefficients, c_i, to the reactants and products: c_1 BaO_2 ⟶ c_2 O_2 + c_3 BaO Set the number of atoms in the reactants equal to the number of atoms in the products for Ba and O: Ba: | c_1 = c_3 O: | 2 c_1 = 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 Substitute the coefficients into the chemical reaction to obtain the balanced equation: Answer: | | 2 BaO_2 ⟶ O_2 + 2 BaO

⟶ +

barium peroxide ⟶ oxygen + barium oxide

Construct the equilibrium constant, K, expression for: BaO_2 ⟶ O_2 + BaO 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 BaO_2 ⟶ O_2 + 2 BaO 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 BaO_2 | 2 | -2 O_2 | 1 | 1 BaO | 2 | 2 Assemble the activity expressions accounting for the state of matter and ν_i: chemical species | c_i | ν_i | activity expression BaO_2 | 2 | -2 | ([BaO2])^(-2) O_2 | 1 | 1 | [O2] BaO | 2 | 2 | ([BaO])^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 = ([BaO2])^(-2) [O2] ([BaO])^2 = ([O2] ([BaO])^2)/([BaO2])^2

Construct the rate of reaction expression for: BaO_2 ⟶ O_2 + BaO 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 BaO_2 ⟶ O_2 + 2 BaO 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 BaO_2 | 2 | -2 O_2 | 1 | 1 BaO | 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 BaO_2 | 2 | -2 | -1/2 (Δ[BaO2])/(Δt) O_2 | 1 | 1 | (Δ[O2])/(Δt) BaO | 2 | 2 | 1/2 (Δ[BaO])/(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[BaO2])/(Δt) = (Δ[O2])/(Δt) = 1/2 (Δ[BaO])/(Δt) (assuming constant volume and no accumulation of intermediates or side products)

| barium peroxide | oxygen | barium oxide formula | BaO_2 | O_2 | BaO name | barium peroxide | oxygen | barium oxide IUPAC name | barium(+2) cation peroxide | molecular oxygen | oxobarium

| barium peroxide | oxygen | barium oxide molar mass | 169.325 g/mol | 31.998 g/mol | 153.326 g/mol phase | solid (at STP) | gas (at STP) | solid (at STP) melting point | 450 °C | -218 °C | 1920 °C boiling point | | -183 °C | density | 4.96 g/cm^3 | 0.001429 g/cm^3 (at 0 °C) | 5.72 g/cm^3 solubility in water | slightly soluble | | surface tension | | 0.01347 N/m | dynamic viscosity | | 2.055×10^-5 Pa s (at 25 °C) | odor | | odorless |