BaBr2 + AgNO2 = AgBr + Ba(NO2)2

BaBr_2 barium bromide + AgNO_2 silver nitrite ⟶ AgBr silver bromide + BaN_2O_4 barium nitrite

Balance the chemical equation algebraically: BaBr_2 + AgNO_2 ⟶ AgBr + BaN_2O_4 Add stoichiometric coefficients, c_i, to the reactants and products: c_1 BaBr_2 + c_2 AgNO_2 ⟶ c_3 AgBr + c_4 BaN_2O_4 Set the number of atoms in the reactants equal to the number of atoms in the products for Ba, Br, Ag, N and O: Ba: | c_1 = c_4 Br: | 2 c_1 = c_3 Ag: | c_2 = c_3 N: | c_2 = 2 c_4 O: | 2 c_2 = 4 c_4 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 = 2 c_3 = 2 c_4 = 1 Substitute the coefficients into the chemical reaction to obtain the balanced equation: Answer: | | BaBr_2 + 2 AgNO_2 ⟶ 2 AgBr + BaN_2O_4

+ ⟶ +

barium bromide + silver nitrite ⟶ silver bromide + barium nitrite

Construct the equilibrium constant, K, expression for: BaBr_2 + AgNO_2 ⟶ AgBr + BaN_2O_4 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: BaBr_2 + 2 AgNO_2 ⟶ 2 AgBr + BaN_2O_4 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 BaBr_2 | 1 | -1 AgNO_2 | 2 | -2 AgBr | 2 | 2 BaN_2O_4 | 1 | 1 Assemble the activity expressions accounting for the state of matter and ν_i: chemical species | c_i | ν_i | activity expression BaBr_2 | 1 | -1 | ([BaBr2])^(-1) AgNO_2 | 2 | -2 | ([AgNO2])^(-2) AgBr | 2 | 2 | ([AgBr])^2 BaN_2O_4 | 1 | 1 | [BaN2O4] 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 = ([BaBr2])^(-1) ([AgNO2])^(-2) ([AgBr])^2 [BaN2O4] = (([AgBr])^2 [BaN2O4])/([BaBr2] ([AgNO2])^2)

Construct the rate of reaction expression for: BaBr_2 + AgNO_2 ⟶ AgBr + BaN_2O_4 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: BaBr_2 + 2 AgNO_2 ⟶ 2 AgBr + BaN_2O_4 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 BaBr_2 | 1 | -1 AgNO_2 | 2 | -2 AgBr | 2 | 2 BaN_2O_4 | 1 | 1 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 BaBr_2 | 1 | -1 | -(Δ[BaBr2])/(Δt) AgNO_2 | 2 | -2 | -1/2 (Δ[AgNO2])/(Δt) AgBr | 2 | 2 | 1/2 (Δ[AgBr])/(Δt) BaN_2O_4 | 1 | 1 | (Δ[BaN2O4])/(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 = -(Δ[BaBr2])/(Δt) = -1/2 (Δ[AgNO2])/(Δt) = 1/2 (Δ[AgBr])/(Δt) = (Δ[BaN2O4])/(Δt) (assuming constant volume and no accumulation of intermediates or side products)

| barium bromide | silver nitrite | silver bromide | barium nitrite formula | BaBr_2 | AgNO_2 | AgBr | BaN_2O_4 name | barium bromide | silver nitrite | silver bromide | barium nitrite IUPAC name | barium(+2) cation dibromide | silver nitrite | bromosilver | barium(+2) cation dinitrite

| barium bromide | silver nitrite | silver bromide | barium nitrite molar mass | 297.13 g/mol | 153.873 g/mol | 187.77 g/mol | 229.34 g/mol phase | solid (at STP) | solid (at STP) | solid (at STP) | solid (at STP) melting point | 860 °C | 140 °C | 432 °C | 269 °C boiling point | 1835 °C | | 1300 °C | density | 4.78 g/cm^3 | 4.453 g/cm^3 | 6.473 g/cm^3 | 3.23 g/cm^3 solubility in water | | | insoluble |