Input interpretation
ZnCl_2 zinc chloride + Ba(OH)_2 barium hydroxide ⟶ BaCl_2 barium chloride + Zn(OH)_2 zinc hydroxide
Balanced equation
Balance the chemical equation algebraically: ZnCl_2 + Ba(OH)_2 ⟶ BaCl_2 + Zn(OH)_2 Add stoichiometric coefficients, c_i, to the reactants and products: c_1 ZnCl_2 + c_2 Ba(OH)_2 ⟶ c_3 BaCl_2 + c_4 Zn(OH)_2 Set the number of atoms in the reactants equal to the number of atoms in the products for Cl, Zn, Ba, H and O: Cl: | 2 c_1 = 2 c_3 Zn: | c_1 = c_4 Ba: | c_2 = c_3 H: | 2 c_2 = 2 c_4 O: | 2 c_2 = 2 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: | | ZnCl_2 + Ba(OH)_2 ⟶ BaCl_2 + Zn(OH)_2
Structures
+ ⟶ +
Names
zinc chloride + barium hydroxide ⟶ barium chloride + zinc hydroxide
Equilibrium constant
Construct the equilibrium constant, K, expression for: ZnCl_2 + Ba(OH)_2 ⟶ BaCl_2 + Zn(OH)_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: ZnCl_2 + Ba(OH)_2 ⟶ BaCl_2 + Zn(OH)_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 ZnCl_2 | 1 | -1 Ba(OH)_2 | 1 | -1 BaCl_2 | 1 | 1 Zn(OH)_2 | 1 | 1 Assemble the activity expressions accounting for the state of matter and ν_i: chemical species | c_i | ν_i | activity expression ZnCl_2 | 1 | -1 | ([ZnCl2])^(-1) Ba(OH)_2 | 1 | -1 | ([Ba(OH)2])^(-1) BaCl_2 | 1 | 1 | [BaCl2] Zn(OH)_2 | 1 | 1 | [Zn(OH)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 = ([ZnCl2])^(-1) ([Ba(OH)2])^(-1) [BaCl2] [Zn(OH)2] = ([BaCl2] [Zn(OH)2])/([ZnCl2] [Ba(OH)2])
Rate of reaction
Construct the rate of reaction expression for: ZnCl_2 + Ba(OH)_2 ⟶ BaCl_2 + Zn(OH)_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: ZnCl_2 + Ba(OH)_2 ⟶ BaCl_2 + Zn(OH)_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 ZnCl_2 | 1 | -1 Ba(OH)_2 | 1 | -1 BaCl_2 | 1 | 1 Zn(OH)_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 ZnCl_2 | 1 | -1 | -(Δ[ZnCl2])/(Δt) Ba(OH)_2 | 1 | -1 | -(Δ[Ba(OH)2])/(Δt) BaCl_2 | 1 | 1 | (Δ[BaCl2])/(Δt) Zn(OH)_2 | 1 | 1 | (Δ[Zn(OH)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[ZnCl2])/(Δt) = -(Δ[Ba(OH)2])/(Δt) = (Δ[BaCl2])/(Δt) = (Δ[Zn(OH)2])/(Δt) (assuming constant volume and no accumulation of intermediates or side products)
Chemical names and formulas
| zinc chloride | barium hydroxide | barium chloride | zinc hydroxide formula | ZnCl_2 | Ba(OH)_2 | BaCl_2 | Zn(OH)_2 Hill formula | Cl_2Zn | BaH_2O_2 | BaCl_2 | H_2O_2Zn name | zinc chloride | barium hydroxide | barium chloride | zinc hydroxide IUPAC name | zinc dichloride | barium(+2) cation dihydroxide | barium(+2) cation dichloride | zinc dihydroxide
Substance properties
| zinc chloride | barium hydroxide | barium chloride | zinc hydroxide molar mass | 136.3 g/mol | 171.34 g/mol | 208.2 g/mol | 99.39 g/mol phase | solid (at STP) | solid (at STP) | solid (at STP) | melting point | 293 °C | 300 °C | 963 °C | density | | 2.2 g/cm^3 | 3.856 g/cm^3 | solubility in water | soluble | | | odor | odorless | | odorless |
Units