Fe + Zn(NO3)2 = Zn + Fe(NO3)2

Fe iron + Zn(NO3)2 ⟶ Zn zinc + Fe(NO_3)_2 iron(II) nitrate

Balance the chemical equation algebraically: Fe + Zn(NO3)2 ⟶ Zn + Fe(NO_3)_2 Add stoichiometric coefficients, c_i, to the reactants and products: c_1 Fe + c_2 Zn(NO3)2 ⟶ c_3 Zn + c_4 Fe(NO_3)_2 Set the number of atoms in the reactants equal to the number of atoms in the products for Fe, Zn, N and O: Fe: | c_1 = c_4 Zn: | c_2 = c_3 N: | 2 c_2 = 2 c_4 O: | 6 c_2 = 6 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 = 1 c_3 = 1 c_4 = 1 Substitute the coefficients into the chemical reaction to obtain the balanced equation: Answer: | | Fe + Zn(NO3)2 ⟶ Zn + Fe(NO_3)_2

+ Zn(NO3)2 ⟶ +

iron + Zn(NO3)2 ⟶ zinc + iron(II) nitrate

Construct the equilibrium constant, K, expression for: Fe + Zn(NO3)2 ⟶ Zn + Fe(NO_3)_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: Fe + Zn(NO3)2 ⟶ Zn + Fe(NO_3)_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 Fe | 1 | -1 Zn(NO3)2 | 1 | -1 Zn | 1 | 1 Fe(NO_3)_2 | 1 | 1 Assemble the activity expressions accounting for the state of matter and ν_i: chemical species | c_i | ν_i | activity expression Fe | 1 | -1 | ([Fe])^(-1) Zn(NO3)2 | 1 | -1 | ([Zn(NO3)2])^(-1) Zn | 1 | 1 | [Zn] Fe(NO_3)_2 | 1 | 1 | [Fe(NO3)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 = ([Fe])^(-1) ([Zn(NO3)2])^(-1) [Zn] [Fe(NO3)2] = ([Zn] [Fe(NO3)2])/([Fe] [Zn(NO3)2])

Construct the rate of reaction expression for: Fe + Zn(NO3)2 ⟶ Zn + Fe(NO_3)_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: Fe + Zn(NO3)2 ⟶ Zn + Fe(NO_3)_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 Fe | 1 | -1 Zn(NO3)2 | 1 | -1 Zn | 1 | 1 Fe(NO_3)_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 Fe | 1 | -1 | -(Δ[Fe])/(Δt) Zn(NO3)2 | 1 | -1 | -(Δ[Zn(NO3)2])/(Δt) Zn | 1 | 1 | (Δ[Zn])/(Δt) Fe(NO_3)_2 | 1 | 1 | (Δ[Fe(NO3)2])/(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[Fe])/(Δt) = -(Δ[Zn(NO3)2])/(Δt) = (Δ[Zn])/(Δt) = (Δ[Fe(NO3)2])/(Δt) (assuming constant volume and no accumulation of intermediates or side products)

| iron | Zn(NO3)2 | zinc | iron(II) nitrate formula | Fe | Zn(NO3)2 | Zn | Fe(NO_3)_2 Hill formula | Fe | N2O6Zn | Zn | FeN_2O_6 name | iron | | zinc | iron(II) nitrate

| iron | Zn(NO3)2 | zinc | iron(II) nitrate molar mass | 55.845 g/mol | 189.4 g/mol | 65.38 g/mol | 179.85 g/mol phase | solid (at STP) | | solid (at STP) | melting point | 1535 °C | | 420 °C | boiling point | 2750 °C | | 907 °C | density | 7.874 g/cm^3 | | 7.14 g/cm^3 | solubility in water | insoluble | | insoluble | odor | | | odorless |