Ca + ZnSO4 = Zn + CaSO4

Ca calcium + ZnSO_4 zinc sulfate ⟶ Zn zinc + CaSO_4 calcium sulfate

Balance the chemical equation algebraically: Ca + ZnSO_4 ⟶ Zn + CaSO_4 Add stoichiometric coefficients, c_i, to the reactants and products: c_1 Ca + c_2 ZnSO_4 ⟶ c_3 Zn + c_4 CaSO_4 Set the number of atoms in the reactants equal to the number of atoms in the products for Ca, O, S and Zn: Ca: | c_1 = c_4 O: | 4 c_2 = 4 c_4 S: | c_2 = c_4 Zn: | 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: | | Ca + ZnSO_4 ⟶ Zn + CaSO_4

+ ⟶ +

calcium + zinc sulfate ⟶ zinc + calcium sulfate

Construct the equilibrium constant, K, expression for: Ca + ZnSO_4 ⟶ Zn + CaSO_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: Ca + ZnSO_4 ⟶ Zn + CaSO_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 Ca | 1 | -1 ZnSO_4 | 1 | -1 Zn | 1 | 1 CaSO_4 | 1 | 1 Assemble the activity expressions accounting for the state of matter and ν_i: chemical species | c_i | ν_i | activity expression Ca | 1 | -1 | ([Ca])^(-1) ZnSO_4 | 1 | -1 | ([ZnSO4])^(-1) Zn | 1 | 1 | [Zn] CaSO_4 | 1 | 1 | [CaSO4] 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 = ([Ca])^(-1) ([ZnSO4])^(-1) [Zn] [CaSO4] = ([Zn] [CaSO4])/([Ca] [ZnSO4])

Construct the rate of reaction expression for: Ca + ZnSO_4 ⟶ Zn + CaSO_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: Ca + ZnSO_4 ⟶ Zn + CaSO_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 Ca | 1 | -1 ZnSO_4 | 1 | -1 Zn | 1 | 1 CaSO_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 Ca | 1 | -1 | -(Δ[Ca])/(Δt) ZnSO_4 | 1 | -1 | -(Δ[ZnSO4])/(Δt) Zn | 1 | 1 | (Δ[Zn])/(Δt) CaSO_4 | 1 | 1 | (Δ[CaSO4])/(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[Ca])/(Δt) = -(Δ[ZnSO4])/(Δt) = (Δ[Zn])/(Δt) = (Δ[CaSO4])/(Δt) (assuming constant volume and no accumulation of intermediates or side products)

| calcium | zinc sulfate | zinc | calcium sulfate formula | Ca | ZnSO_4 | Zn | CaSO_4 Hill formula | Ca | O_4SZn | Zn | CaO_4S name | calcium | zinc sulfate | zinc | calcium sulfate

| calcium | zinc sulfate | zinc | calcium sulfate molar mass | 40.078 g/mol | 161.4 g/mol | 65.38 g/mol | 136.13 g/mol phase | solid (at STP) | | solid (at STP) | melting point | 850 °C | | 420 °C | boiling point | 1484 °C | | 907 °C | density | 1.54 g/cm^3 | 1.005 g/cm^3 | 7.14 g/cm^3 | solubility in water | decomposes | soluble | insoluble | slightly soluble odor | | odorless | odorless | odorless