N2O3H2O = HNO2

N2O3H2O ⟶ HNO_2 nitrous acid

Balance the chemical equation algebraically: N2O3H2O ⟶ HNO_2 Add stoichiometric coefficients, c_i, to the reactants and products: c_1 N2O3H2O ⟶ c_2 HNO_2 Set the number of atoms in the reactants equal to the number of atoms in the products for N, O and H: N: | 2 c_1 = c_2 O: | 4 c_1 = 2 c_2 H: | 2 c_1 = 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_1 = 1 and solve the system of equations for the remaining coefficients: c_1 = 1 c_2 = 2 Substitute the coefficients into the chemical reaction to obtain the balanced equation: Answer: | | N2O3H2O ⟶ 2 HNO_2

N2O3H2O ⟶

N2O3H2O ⟶ nitrous acid

Construct the equilibrium constant, K, expression for: N2O3H2O ⟶ HNO_2 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: N2O3H2O ⟶ 2 HNO_2 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 N2O3H2O | 1 | -1 HNO_2 | 2 | 2 Assemble the activity expressions accounting for the state of matter and ν_i: chemical species | c_i | ν_i | activity expression N2O3H2O | 1 | -1 | ([N2O3H2O])^(-1) HNO_2 | 2 | 2 | ([HNO2])^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 = ([N2O3H2O])^(-1) ([HNO2])^2 = ([HNO2])^2/([N2O3H2O])

Construct the rate of reaction expression for: N2O3H2O ⟶ HNO_2 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: N2O3H2O ⟶ 2 HNO_2 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 N2O3H2O | 1 | -1 HNO_2 | 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 N2O3H2O | 1 | -1 | -(Δ[N2O3H2O])/(Δt) HNO_2 | 2 | 2 | 1/2 (Δ[HNO2])/(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[N2O3H2O])/(Δt) = 1/2 (Δ[HNO2])/(Δt) (assuming constant volume and no accumulation of intermediates or side products)

| N2O3H2O | nitrous acid formula | N2O3H2O | HNO_2 Hill formula | H2N2O4 | HNO_2 name | | nitrous acid

| N2O3H2O | nitrous acid molar mass | 94.03 g/mol | 47.013 g/mol