Input interpretation
AgNO_3 silver nitrate + ZnBr_2 zinc bromide ⟶ Zn(NO3)2 + AgBr silver bromide
Balanced equation
Balance the chemical equation algebraically: AgNO_3 + ZnBr_2 ⟶ Zn(NO3)2 + AgBr Add stoichiometric coefficients, c_i, to the reactants and products: c_1 AgNO_3 + c_2 ZnBr_2 ⟶ c_3 Zn(NO3)2 + c_4 AgBr Set the number of atoms in the reactants equal to the number of atoms in the products for Ag, N, O, Br and Zn: Ag: | c_1 = c_4 N: | c_1 = 2 c_3 O: | 3 c_1 = 6 c_3 Br: | 2 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_2 = 1 and solve the system of equations for the remaining coefficients: c_1 = 2 c_2 = 1 c_3 = 1 c_4 = 2 Substitute the coefficients into the chemical reaction to obtain the balanced equation: Answer: | | 2 AgNO_3 + ZnBr_2 ⟶ Zn(NO3)2 + 2 AgBr
Structures
+ ⟶ Zn(NO3)2 +
Names
silver nitrate + zinc bromide ⟶ Zn(NO3)2 + silver bromide
Equilibrium constant
Construct the equilibrium constant, K, expression for: AgNO_3 + ZnBr_2 ⟶ Zn(NO3)2 + AgBr 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: 2 AgNO_3 + ZnBr_2 ⟶ Zn(NO3)2 + 2 AgBr 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 AgNO_3 | 2 | -2 ZnBr_2 | 1 | -1 Zn(NO3)2 | 1 | 1 AgBr | 2 | 2 Assemble the activity expressions accounting for the state of matter and ν_i: chemical species | c_i | ν_i | activity expression AgNO_3 | 2 | -2 | ([AgNO3])^(-2) ZnBr_2 | 1 | -1 | ([ZnBr2])^(-1) Zn(NO3)2 | 1 | 1 | [Zn(NO3)2] AgBr | 2 | 2 | ([AgBr])^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 = ([AgNO3])^(-2) ([ZnBr2])^(-1) [Zn(NO3)2] ([AgBr])^2 = ([Zn(NO3)2] ([AgBr])^2)/(([AgNO3])^2 [ZnBr2])
Rate of reaction
Construct the rate of reaction expression for: AgNO_3 + ZnBr_2 ⟶ Zn(NO3)2 + AgBr 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: 2 AgNO_3 + ZnBr_2 ⟶ Zn(NO3)2 + 2 AgBr 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 AgNO_3 | 2 | -2 ZnBr_2 | 1 | -1 Zn(NO3)2 | 1 | 1 AgBr | 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 AgNO_3 | 2 | -2 | -1/2 (Δ[AgNO3])/(Δt) ZnBr_2 | 1 | -1 | -(Δ[ZnBr2])/(Δt) Zn(NO3)2 | 1 | 1 | (Δ[Zn(NO3)2])/(Δt) AgBr | 2 | 2 | 1/2 (Δ[AgBr])/(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 = -1/2 (Δ[AgNO3])/(Δt) = -(Δ[ZnBr2])/(Δt) = (Δ[Zn(NO3)2])/(Δt) = 1/2 (Δ[AgBr])/(Δt) (assuming constant volume and no accumulation of intermediates or side products)
Chemical names and formulas
| silver nitrate | zinc bromide | Zn(NO3)2 | silver bromide formula | AgNO_3 | ZnBr_2 | Zn(NO3)2 | AgBr Hill formula | AgNO_3 | Br_2Zn | N2O6Zn | AgBr name | silver nitrate | zinc bromide | | silver bromide IUPAC name | silver nitrate | dibromozinc | | bromosilver
Substance properties
| silver nitrate | zinc bromide | Zn(NO3)2 | silver bromide molar mass | 169.87 g/mol | 225.2 g/mol | 189.4 g/mol | 187.77 g/mol phase | solid (at STP) | solid (at STP) | | solid (at STP) melting point | 212 °C | 394 °C | | 432 °C boiling point | | 675 °C | | 1300 °C density | | 4.22 g/cm^3 | | 6.473 g/cm^3 solubility in water | soluble | | | insoluble odor | odorless | | |
Units