NaNO3 + Pb = PbO + Na(NO2)

NaNO_3 sodium nitrate + Pb lead ⟶ PbO lead monoxide + NaNO_2 sodium nitrite

Balance the chemical equation algebraically: NaNO_3 + Pb ⟶ PbO + NaNO_2 Add stoichiometric coefficients, c_i, to the reactants and products: c_1 NaNO_3 + c_2 Pb ⟶ c_3 PbO + c_4 NaNO_2 Set the number of atoms in the reactants equal to the number of atoms in the products for N, Na, O and Pb: N: | c_1 = c_4 Na: | c_1 = c_4 O: | 3 c_1 = c_3 + 2 c_4 Pb: | 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_1 = 1 and solve the system of equations for the remaining coefficients: c_1 = 1 c_2 = 1 c_3 = 1 c_4 = 1 Substitute the coefficients into the chemical reaction to obtain the balanced equation: Answer: | | NaNO_3 + Pb ⟶ PbO + NaNO_2

+ ⟶ +

sodium nitrate + lead ⟶ lead monoxide + sodium nitrite

Construct the equilibrium constant, K, expression for: NaNO_3 + Pb ⟶ PbO + NaNO_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: NaNO_3 + Pb ⟶ PbO + NaNO_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 NaNO_3 | 1 | -1 Pb | 1 | -1 PbO | 1 | 1 NaNO_2 | 1 | 1 Assemble the activity expressions accounting for the state of matter and ν_i: chemical species | c_i | ν_i | activity expression NaNO_3 | 1 | -1 | ([NaNO3])^(-1) Pb | 1 | -1 | ([Pb])^(-1) PbO | 1 | 1 | [PbO] NaNO_2 | 1 | 1 | [NaNO2] 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 = ([NaNO3])^(-1) ([Pb])^(-1) [PbO] [NaNO2] = ([PbO] [NaNO2])/([NaNO3] [Pb])

Construct the rate of reaction expression for: NaNO_3 + Pb ⟶ PbO + NaNO_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: NaNO_3 + Pb ⟶ PbO + NaNO_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 NaNO_3 | 1 | -1 Pb | 1 | -1 PbO | 1 | 1 NaNO_2 | 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 NaNO_3 | 1 | -1 | -(Δ[NaNO3])/(Δt) Pb | 1 | -1 | -(Δ[Pb])/(Δt) PbO | 1 | 1 | (Δ[PbO])/(Δt) NaNO_2 | 1 | 1 | (Δ[NaNO2])/(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[NaNO3])/(Δt) = -(Δ[Pb])/(Δt) = (Δ[PbO])/(Δt) = (Δ[NaNO2])/(Δt) (assuming constant volume and no accumulation of intermediates or side products)

| sodium nitrate | lead | lead monoxide | sodium nitrite formula | NaNO_3 | Pb | PbO | NaNO_2 Hill formula | NNaO_3 | Pb | OPb | NNaO_2 name | sodium nitrate | lead | lead monoxide | sodium nitrite

| sodium nitrate | lead | lead monoxide | sodium nitrite molar mass | 84.994 g/mol | 207.2 g/mol | 223.2 g/mol | 68.995 g/mol phase | solid (at STP) | solid (at STP) | solid (at STP) | solid (at STP) melting point | 306 °C | 327.4 °C | 886 °C | 271 °C boiling point | | 1740 °C | 1470 °C | density | 2.26 g/cm^3 | 11.34 g/cm^3 | 9.5 g/cm^3 | 2.168 g/cm^3 solubility in water | soluble | insoluble | insoluble | dynamic viscosity | 0.003 Pa s (at 250 °C) | 0.00183 Pa s (at 38 °C) | 1.45×10^-4 Pa s (at 1000 °C) |