BaCl2 + Na2(SO4) = Ba(SO4) + ClNa

BaCl_2 barium chloride + Na_2SO_4 sodium sulfate ⟶ BaSO_4 barium sulfate + NaCl sodium chloride

Balance the chemical equation algebraically: BaCl_2 + Na_2SO_4 ⟶ BaSO_4 + NaCl Add stoichiometric coefficients, c_i, to the reactants and products: c_1 BaCl_2 + c_2 Na_2SO_4 ⟶ c_3 BaSO_4 + c_4 NaCl Set the number of atoms in the reactants equal to the number of atoms in the products for Ba, Cl, Na, O and S: Ba: | c_1 = c_3 Cl: | 2 c_1 = c_4 Na: | 2 c_2 = c_4 O: | 4 c_2 = 4 c_3 S: | 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 = 2 Substitute the coefficients into the chemical reaction to obtain the balanced equation: Answer: | | BaCl_2 + Na_2SO_4 ⟶ BaSO_4 + 2 NaCl

+ ⟶ +

barium chloride + sodium sulfate ⟶ barium sulfate + sodium chloride

| barium chloride | sodium sulfate | barium sulfate | sodium chloride molecular enthalpy | -855 kJ/mol | -1387 kJ/mol | -1473 kJ/mol | -411.2 kJ/mol total enthalpy | -855 kJ/mol | -1387 kJ/mol | -1473 kJ/mol | -822.4 kJ/mol | H_initial = -2242 kJ/mol | | H_final = -2296 kJ/mol | ΔH_rxn^0 | -2296 kJ/mol - -2242 kJ/mol = -53.5 kJ/mol (exothermic) | | |

| barium chloride | sodium sulfate | barium sulfate | sodium chloride molecular free energy | -806.7 kJ/mol | -1270 kJ/mol | -1362 kJ/mol | -384.1 kJ/mol total free energy | -806.7 kJ/mol | -1270 kJ/mol | -1362 kJ/mol | -768.2 kJ/mol | G_initial = -2077 kJ/mol | | G_final = -2130 kJ/mol | ΔG_rxn^0 | -2130 kJ/mol - -2077 kJ/mol = -53.5 kJ/mol (exergonic) | | |

Construct the equilibrium constant, K, expression for: BaCl_2 + Na_2SO_4 ⟶ BaSO_4 + NaCl 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: BaCl_2 + Na_2SO_4 ⟶ BaSO_4 + 2 NaCl 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 BaCl_2 | 1 | -1 Na_2SO_4 | 1 | -1 BaSO_4 | 1 | 1 NaCl | 2 | 2 Assemble the activity expressions accounting for the state of matter and ν_i: chemical species | c_i | ν_i | activity expression BaCl_2 | 1 | -1 | ([BaCl2])^(-1) Na_2SO_4 | 1 | -1 | ([Na2SO4])^(-1) BaSO_4 | 1 | 1 | [BaSO4] NaCl | 2 | 2 | ([NaCl])^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 = ([BaCl2])^(-1) ([Na2SO4])^(-1) [BaSO4] ([NaCl])^2 = ([BaSO4] ([NaCl])^2)/([BaCl2] [Na2SO4])

Construct the rate of reaction expression for: BaCl_2 + Na_2SO_4 ⟶ BaSO_4 + NaCl 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: BaCl_2 + Na_2SO_4 ⟶ BaSO_4 + 2 NaCl 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 BaCl_2 | 1 | -1 Na_2SO_4 | 1 | -1 BaSO_4 | 1 | 1 NaCl | 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 BaCl_2 | 1 | -1 | -(Δ[BaCl2])/(Δt) Na_2SO_4 | 1 | -1 | -(Δ[Na2SO4])/(Δt) BaSO_4 | 1 | 1 | (Δ[BaSO4])/(Δt) NaCl | 2 | 2 | 1/2 (Δ[NaCl])/(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[BaCl2])/(Δt) = -(Δ[Na2SO4])/(Δt) = (Δ[BaSO4])/(Δt) = 1/2 (Δ[NaCl])/(Δt) (assuming constant volume and no accumulation of intermediates or side products)

| barium chloride | sodium sulfate | barium sulfate | sodium chloride formula | BaCl_2 | Na_2SO_4 | BaSO_4 | NaCl Hill formula | BaCl_2 | Na_2O_4S | BaO_4S | ClNa name | barium chloride | sodium sulfate | barium sulfate | sodium chloride IUPAC name | barium(+2) cation dichloride | disodium sulfate | barium(+2) cation sulfate | sodium chloride

| barium chloride | sodium sulfate | barium sulfate | sodium chloride molar mass | 208.2 g/mol | 142.04 g/mol | 233.38 g/mol | 58.44 g/mol phase | solid (at STP) | solid (at STP) | solid (at STP) | solid (at STP) melting point | 963 °C | 884 °C | 1345 °C | 801 °C boiling point | | 1429 °C | | 1413 °C density | 3.856 g/cm^3 | 2.68 g/cm^3 | 4.5 g/cm^3 | 2.16 g/cm^3 solubility in water | | soluble | insoluble | soluble odor | odorless | | | odorless