Na2SO4 + CaCl2 = NaCl + CaSO4

Na_2SO_4 sodium sulfate + CaCl_2 calcium chloride ⟶ NaCl sodium chloride + CaSO_4 calcium sulfate

Balance the chemical equation algebraically: Na_2SO_4 + CaCl_2 ⟶ NaCl + CaSO_4 Add stoichiometric coefficients, c_i, to the reactants and products: c_1 Na_2SO_4 + c_2 CaCl_2 ⟶ c_3 NaCl + c_4 CaSO_4 Set the number of atoms in the reactants equal to the number of atoms in the products for Na, O, S, Ca and Cl: Na: | 2 c_1 = c_3 O: | 4 c_1 = 4 c_4 S: | c_1 = c_4 Ca: | c_2 = c_4 Cl: | 2 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 = 2 c_4 = 1 Substitute the coefficients into the chemical reaction to obtain the balanced equation: Answer: | | Na_2SO_4 + CaCl_2 ⟶ 2 NaCl + CaSO_4

+ ⟶ +

sodium sulfate + calcium chloride ⟶ sodium chloride + calcium sulfate

Construct the equilibrium constant, K, expression for: Na_2SO_4 + CaCl_2 ⟶ NaCl + 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: Na_2SO_4 + CaCl_2 ⟶ 2 NaCl + 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 Na_2SO_4 | 1 | -1 CaCl_2 | 1 | -1 NaCl | 2 | 2 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 Na_2SO_4 | 1 | -1 | ([Na2SO4])^(-1) CaCl_2 | 1 | -1 | ([CaCl2])^(-1) NaCl | 2 | 2 | ([NaCl])^2 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 = ([Na2SO4])^(-1) ([CaCl2])^(-1) ([NaCl])^2 [CaSO4] = (([NaCl])^2 [CaSO4])/([Na2SO4] [CaCl2])

Construct the rate of reaction expression for: Na_2SO_4 + CaCl_2 ⟶ NaCl + 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: Na_2SO_4 + CaCl_2 ⟶ 2 NaCl + 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 Na_2SO_4 | 1 | -1 CaCl_2 | 1 | -1 NaCl | 2 | 2 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 Na_2SO_4 | 1 | -1 | -(Δ[Na2SO4])/(Δt) CaCl_2 | 1 | -1 | -(Δ[CaCl2])/(Δt) NaCl | 2 | 2 | 1/2 (Δ[NaCl])/(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[Na2SO4])/(Δt) = -(Δ[CaCl2])/(Δt) = 1/2 (Δ[NaCl])/(Δt) = (Δ[CaSO4])/(Δt) (assuming constant volume and no accumulation of intermediates or side products)

| sodium sulfate | calcium chloride | sodium chloride | calcium sulfate formula | Na_2SO_4 | CaCl_2 | NaCl | CaSO_4 Hill formula | Na_2O_4S | CaCl_2 | ClNa | CaO_4S name | sodium sulfate | calcium chloride | sodium chloride | calcium sulfate IUPAC name | disodium sulfate | calcium dichloride | sodium chloride | calcium sulfate

| sodium sulfate | calcium chloride | sodium chloride | calcium sulfate molar mass | 142.04 g/mol | 111 g/mol | 58.44 g/mol | 136.13 g/mol phase | solid (at STP) | solid (at STP) | solid (at STP) | melting point | 884 °C | 772 °C | 801 °C | boiling point | 1429 °C | | 1413 °C | density | 2.68 g/cm^3 | 2.15 g/cm^3 | 2.16 g/cm^3 | solubility in water | soluble | soluble | soluble | slightly soluble odor | | | odorless | odorless