HNO3 + NaBiO3 + Cr(NO3)3 = H2O + NaNO3 + Bi(NO3)3 + Na2CrO7

HNO_3 nitric acid + NaBiO_3 sodium bismuthate + CrN_3O_9 chromium nitrate ⟶ H_2O water + NaNO_3 sodium nitrate + Bi(NO3)3 + Na2CrO7

Balance the chemical equation algebraically: HNO_3 + NaBiO_3 + CrN_3O_9 ⟶ H_2O + NaNO_3 + Bi(NO3)3 + Na2CrO7 Add stoichiometric coefficients, c_i, to the reactants and products: c_1 HNO_3 + c_2 NaBiO_3 + c_3 CrN_3O_9 ⟶ c_4 H_2O + c_5 NaNO_3 + c_6 Bi(NO3)3 + c_7 Na2CrO7 Set the number of atoms in the reactants equal to the number of atoms in the products for H, N, O, Bi, Na and Cr: H: | c_1 = 2 c_4 N: | c_1 + 3 c_3 = c_5 + 3 c_6 O: | 3 c_1 + 3 c_2 + 9 c_3 = c_4 + 3 c_5 + 9 c_6 + 7 c_7 Bi: | c_2 = c_6 Na: | c_2 = c_5 + 2 c_7 Cr: | c_3 = c_7 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_3 = 1 and solve the system of equations for the remaining coefficients: c_1 = 13 c_2 = 9/2 c_3 = 1 c_4 = 13/2 c_5 = 5/2 c_6 = 9/2 c_7 = 1 Multiply by the least common denominator, 2, to eliminate fractional coefficients: c_1 = 26 c_2 = 9 c_3 = 2 c_4 = 13 c_5 = 5 c_6 = 9 c_7 = 2 Substitute the coefficients into the chemical reaction to obtain the balanced equation: Answer: | | 26 HNO_3 + 9 NaBiO_3 + 2 CrN_3O_9 ⟶ 13 H_2O + 5 NaNO_3 + 9 Bi(NO3)3 + 2 Na2CrO7

+ + ⟶ + + Bi(NO3)3 + Na2CrO7

nitric acid + sodium bismuthate + chromium nitrate ⟶ water + sodium nitrate + Bi(NO3)3 + Na2CrO7

Construct the equilibrium constant, K, expression for: HNO_3 + NaBiO_3 + CrN_3O_9 ⟶ H_2O + NaNO_3 + Bi(NO3)3 + Na2CrO7 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: 26 HNO_3 + 9 NaBiO_3 + 2 CrN_3O_9 ⟶ 13 H_2O + 5 NaNO_3 + 9 Bi(NO3)3 + 2 Na2CrO7 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 HNO_3 | 26 | -26 NaBiO_3 | 9 | -9 CrN_3O_9 | 2 | -2 H_2O | 13 | 13 NaNO_3 | 5 | 5 Bi(NO3)3 | 9 | 9 Na2CrO7 | 2 | 2 Assemble the activity expressions accounting for the state of matter and ν_i: chemical species | c_i | ν_i | activity expression HNO_3 | 26 | -26 | ([HNO3])^(-26) NaBiO_3 | 9 | -9 | ([NaBiO3])^(-9) CrN_3O_9 | 2 | -2 | ([CrN3O9])^(-2) H_2O | 13 | 13 | ([H2O])^13 NaNO_3 | 5 | 5 | ([NaNO3])^5 Bi(NO3)3 | 9 | 9 | ([Bi(NO3)3])^9 Na2CrO7 | 2 | 2 | ([Na2CrO7])^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 = ([HNO3])^(-26) ([NaBiO3])^(-9) ([CrN3O9])^(-2) ([H2O])^13 ([NaNO3])^5 ([Bi(NO3)3])^9 ([Na2CrO7])^2 = (([H2O])^13 ([NaNO3])^5 ([Bi(NO3)3])^9 ([Na2CrO7])^2)/(([HNO3])^26 ([NaBiO3])^9 ([CrN3O9])^2)

Construct the rate of reaction expression for: HNO_3 + NaBiO_3 + CrN_3O_9 ⟶ H_2O + NaNO_3 + Bi(NO3)3 + Na2CrO7 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: 26 HNO_3 + 9 NaBiO_3 + 2 CrN_3O_9 ⟶ 13 H_2O + 5 NaNO_3 + 9 Bi(NO3)3 + 2 Na2CrO7 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 HNO_3 | 26 | -26 NaBiO_3 | 9 | -9 CrN_3O_9 | 2 | -2 H_2O | 13 | 13 NaNO_3 | 5 | 5 Bi(NO3)3 | 9 | 9 Na2CrO7 | 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 HNO_3 | 26 | -26 | -1/26 (Δ[HNO3])/(Δt) NaBiO_3 | 9 | -9 | -1/9 (Δ[NaBiO3])/(Δt) CrN_3O_9 | 2 | -2 | -1/2 (Δ[CrN3O9])/(Δt) H_2O | 13 | 13 | 1/13 (Δ[H2O])/(Δt) NaNO_3 | 5 | 5 | 1/5 (Δ[NaNO3])/(Δt) Bi(NO3)3 | 9 | 9 | 1/9 (Δ[Bi(NO3)3])/(Δt) Na2CrO7 | 2 | 2 | 1/2 (Δ[Na2CrO7])/(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 = -1/26 (Δ[HNO3])/(Δt) = -1/9 (Δ[NaBiO3])/(Δt) = -1/2 (Δ[CrN3O9])/(Δt) = 1/13 (Δ[H2O])/(Δt) = 1/5 (Δ[NaNO3])/(Δt) = 1/9 (Δ[Bi(NO3)3])/(Δt) = 1/2 (Δ[Na2CrO7])/(Δt) (assuming constant volume and no accumulation of intermediates or side products)

| nitric acid | sodium bismuthate | chromium nitrate | water | sodium nitrate | Bi(NO3)3 | Na2CrO7 formula | HNO_3 | NaBiO_3 | CrN_3O_9 | H_2O | NaNO_3 | Bi(NO3)3 | Na2CrO7 Hill formula | HNO_3 | BiNaO_3 | CrN_3O_9 | H_2O | NNaO_3 | BiN3O9 | CrNa2O7 name | nitric acid | sodium bismuthate | chromium nitrate | water | sodium nitrate | | IUPAC name | nitric acid | sodium oxido-dioxobismuth | chromium(+3) cation trinitrate | water | sodium nitrate | |

| nitric acid | sodium bismuthate | chromium nitrate | water | sodium nitrate | Bi(NO3)3 | Na2CrO7 molar mass | 63.012 g/mol | 279.967 g/mol | 238.01 g/mol | 18.015 g/mol | 84.994 g/mol | 394.99 g/mol | 209.97 g/mol phase | liquid (at STP) | | solid (at STP) | liquid (at STP) | solid (at STP) | | melting point | -41.6 °C | | 66 °C | 0 °C | 306 °C | | boiling point | 83 °C | | | 99.9839 °C | | | density | 1.5129 g/cm^3 | | 1.8 g/cm^3 | 1 g/cm^3 | 2.26 g/cm^3 | | solubility in water | miscible | insoluble | soluble | | soluble | | surface tension | | | | 0.0728 N/m | | | dynamic viscosity | 7.6×10^-4 Pa s (at 25 °C) | | | 8.9×10^-4 Pa s (at 25 °C) | 0.003 Pa s (at 250 °C) | | odor | | | | odorless | | |