H2SO4 + KI + NaNO3 = H2O + K2SO4 + I2 + NO + Na2SO4

H_2SO_4 sulfuric acid + KI potassium iodide + NaNO_3 sodium nitrate ⟶ H_2O water + K_2SO_4 potassium sulfate + I_2 iodine + NO nitric oxide + Na_2SO_4 sodium sulfate

Balance the chemical equation algebraically: H_2SO_4 + KI + NaNO_3 ⟶ H_2O + K_2SO_4 + I_2 + NO + Na_2SO_4 Add stoichiometric coefficients, c_i, to the reactants and products: c_1 H_2SO_4 + c_2 KI + c_3 NaNO_3 ⟶ c_4 H_2O + c_5 K_2SO_4 + c_6 I_2 + c_7 NO + c_8 Na_2SO_4 Set the number of atoms in the reactants equal to the number of atoms in the products for H, O, S, I, K, N and Na: H: | 2 c_1 = 2 c_4 O: | 4 c_1 + 3 c_3 = c_4 + 4 c_5 + c_7 + 4 c_8 S: | c_1 = c_5 + c_8 I: | c_2 = 2 c_6 K: | c_2 = 2 c_5 N: | c_3 = c_7 Na: | c_3 = 2 c_8 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_8 = 1 and solve the system of equations for the remaining coefficients: c_1 = 4 c_2 = 6 c_3 = 2 c_4 = 4 c_5 = 3 c_6 = 3 c_7 = 2 c_8 = 1 Substitute the coefficients into the chemical reaction to obtain the balanced equation: Answer: | | 4 H_2SO_4 + 6 KI + 2 NaNO_3 ⟶ 4 H_2O + 3 K_2SO_4 + 3 I_2 + 2 NO + Na_2SO_4

+ + ⟶ + + + +

sulfuric acid + potassium iodide + sodium nitrate ⟶ water + potassium sulfate + iodine + nitric oxide + sodium sulfate

Construct the equilibrium constant, K, expression for: H_2SO_4 + KI + NaNO_3 ⟶ H_2O + K_2SO_4 + I_2 + NO + Na_2SO_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: 4 H_2SO_4 + 6 KI + 2 NaNO_3 ⟶ 4 H_2O + 3 K_2SO_4 + 3 I_2 + 2 NO + Na_2SO_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 H_2SO_4 | 4 | -4 KI | 6 | -6 NaNO_3 | 2 | -2 H_2O | 4 | 4 K_2SO_4 | 3 | 3 I_2 | 3 | 3 NO | 2 | 2 Na_2SO_4 | 1 | 1 Assemble the activity expressions accounting for the state of matter and ν_i: chemical species | c_i | ν_i | activity expression H_2SO_4 | 4 | -4 | ([H2SO4])^(-4) KI | 6 | -6 | ([KI])^(-6) NaNO_3 | 2 | -2 | ([NaNO3])^(-2) H_2O | 4 | 4 | ([H2O])^4 K_2SO_4 | 3 | 3 | ([K2SO4])^3 I_2 | 3 | 3 | ([I2])^3 NO | 2 | 2 | ([NO])^2 Na_2SO_4 | 1 | 1 | [Na2SO4] 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 = ([H2SO4])^(-4) ([KI])^(-6) ([NaNO3])^(-2) ([H2O])^4 ([K2SO4])^3 ([I2])^3 ([NO])^2 [Na2SO4] = (([H2O])^4 ([K2SO4])^3 ([I2])^3 ([NO])^2 [Na2SO4])/(([H2SO4])^4 ([KI])^6 ([NaNO3])^2)

Construct the rate of reaction expression for: H_2SO_4 + KI + NaNO_3 ⟶ H_2O + K_2SO_4 + I_2 + NO + Na_2SO_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: 4 H_2SO_4 + 6 KI + 2 NaNO_3 ⟶ 4 H_2O + 3 K_2SO_4 + 3 I_2 + 2 NO + Na_2SO_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 H_2SO_4 | 4 | -4 KI | 6 | -6 NaNO_3 | 2 | -2 H_2O | 4 | 4 K_2SO_4 | 3 | 3 I_2 | 3 | 3 NO | 2 | 2 Na_2SO_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 H_2SO_4 | 4 | -4 | -1/4 (Δ[H2SO4])/(Δt) KI | 6 | -6 | -1/6 (Δ[KI])/(Δt) NaNO_3 | 2 | -2 | -1/2 (Δ[NaNO3])/(Δt) H_2O | 4 | 4 | 1/4 (Δ[H2O])/(Δt) K_2SO_4 | 3 | 3 | 1/3 (Δ[K2SO4])/(Δt) I_2 | 3 | 3 | 1/3 (Δ[I2])/(Δt) NO | 2 | 2 | 1/2 (Δ[NO])/(Δt) Na_2SO_4 | 1 | 1 | (Δ[Na2SO4])/(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 = -1/4 (Δ[H2SO4])/(Δt) = -1/6 (Δ[KI])/(Δt) = -1/2 (Δ[NaNO3])/(Δt) = 1/4 (Δ[H2O])/(Δt) = 1/3 (Δ[K2SO4])/(Δt) = 1/3 (Δ[I2])/(Δt) = 1/2 (Δ[NO])/(Δt) = (Δ[Na2SO4])/(Δt) (assuming constant volume and no accumulation of intermediates or side products)

| sulfuric acid | potassium iodide | sodium nitrate | water | potassium sulfate | iodine | nitric oxide | sodium sulfate formula | H_2SO_4 | KI | NaNO_3 | H_2O | K_2SO_4 | I_2 | NO | Na_2SO_4 Hill formula | H_2O_4S | IK | NNaO_3 | H_2O | K_2O_4S | I_2 | NO | Na_2O_4S name | sulfuric acid | potassium iodide | sodium nitrate | water | potassium sulfate | iodine | nitric oxide | sodium sulfate IUPAC name | sulfuric acid | potassium iodide | sodium nitrate | water | dipotassium sulfate | molecular iodine | nitric oxide | disodium sulfate