Input interpretation
KNO_3 potassium nitrate + Na_2CO_3 soda ash + ZnS zinc sulfide ⟶ Na_2SO_4 sodium sulfate + KNO_2 potassium nitrite + ZnCO_3 zinc carbonate
Balanced equation
Balance the chemical equation algebraically: KNO_3 + Na_2CO_3 + ZnS ⟶ Na_2SO_4 + KNO_2 + ZnCO_3 Add stoichiometric coefficients, c_i, to the reactants and products: c_1 KNO_3 + c_2 Na_2CO_3 + c_3 ZnS ⟶ c_4 Na_2SO_4 + c_5 KNO_2 + c_6 ZnCO_3 Set the number of atoms in the reactants equal to the number of atoms in the products for K, N, O, C, Na, S and Zn: K: | c_1 = c_5 N: | c_1 = c_5 O: | 3 c_1 + 3 c_2 = 4 c_4 + 2 c_5 + 3 c_6 C: | c_2 = c_6 Na: | 2 c_2 = 2 c_4 S: | c_3 = c_4 Zn: | c_3 = c_6 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 = 4 c_2 = 1 c_3 = 1 c_4 = 1 c_5 = 4 c_6 = 1 Substitute the coefficients into the chemical reaction to obtain the balanced equation: Answer: | | 4 KNO_3 + Na_2CO_3 + ZnS ⟶ Na_2SO_4 + 4 KNO_2 + ZnCO_3
Structures
+ + ⟶ + +
Names
potassium nitrate + soda ash + zinc sulfide ⟶ sodium sulfate + potassium nitrite + zinc carbonate
Equilibrium constant
Construct the equilibrium constant, K, expression for: KNO_3 + Na_2CO_3 + ZnS ⟶ Na_2SO_4 + KNO_2 + ZnCO_3 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: 4 KNO_3 + Na_2CO_3 + ZnS ⟶ Na_2SO_4 + 4 KNO_2 + ZnCO_3 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 KNO_3 | 4 | -4 Na_2CO_3 | 1 | -1 ZnS | 1 | -1 Na_2SO_4 | 1 | 1 KNO_2 | 4 | 4 ZnCO_3 | 1 | 1 Assemble the activity expressions accounting for the state of matter and ν_i: chemical species | c_i | ν_i | activity expression KNO_3 | 4 | -4 | ([KNO3])^(-4) Na_2CO_3 | 1 | -1 | ([Na2CO3])^(-1) ZnS | 1 | -1 | ([ZnS])^(-1) Na_2SO_4 | 1 | 1 | [Na2SO4] KNO_2 | 4 | 4 | ([KNO2])^4 ZnCO_3 | 1 | 1 | [ZnCO3] 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 = ([KNO3])^(-4) ([Na2CO3])^(-1) ([ZnS])^(-1) [Na2SO4] ([KNO2])^4 [ZnCO3] = ([Na2SO4] ([KNO2])^4 [ZnCO3])/(([KNO3])^4 [Na2CO3] [ZnS])
Rate of reaction
Construct the rate of reaction expression for: KNO_3 + Na_2CO_3 + ZnS ⟶ Na_2SO_4 + KNO_2 + ZnCO_3 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: 4 KNO_3 + Na_2CO_3 + ZnS ⟶ Na_2SO_4 + 4 KNO_2 + ZnCO_3 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 KNO_3 | 4 | -4 Na_2CO_3 | 1 | -1 ZnS | 1 | -1 Na_2SO_4 | 1 | 1 KNO_2 | 4 | 4 ZnCO_3 | 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 KNO_3 | 4 | -4 | -1/4 (Δ[KNO3])/(Δt) Na_2CO_3 | 1 | -1 | -(Δ[Na2CO3])/(Δt) ZnS | 1 | -1 | -(Δ[ZnS])/(Δt) Na_2SO_4 | 1 | 1 | (Δ[Na2SO4])/(Δt) KNO_2 | 4 | 4 | 1/4 (Δ[KNO2])/(Δt) ZnCO_3 | 1 | 1 | (Δ[ZnCO3])/(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 = -1/4 (Δ[KNO3])/(Δt) = -(Δ[Na2CO3])/(Δt) = -(Δ[ZnS])/(Δt) = (Δ[Na2SO4])/(Δt) = 1/4 (Δ[KNO2])/(Δt) = (Δ[ZnCO3])/(Δt) (assuming constant volume and no accumulation of intermediates or side products)
Chemical names and formulas
| potassium nitrate | soda ash | zinc sulfide | sodium sulfate | potassium nitrite | zinc carbonate formula | KNO_3 | Na_2CO_3 | ZnS | Na_2SO_4 | KNO_2 | ZnCO_3 Hill formula | KNO_3 | CNa_2O_3 | SZn | Na_2O_4S | KNO_2 | CO_3Zn name | potassium nitrate | soda ash | zinc sulfide | sodium sulfate | potassium nitrite | zinc carbonate IUPAC name | potassium nitrate | disodium carbonate | thioxozinc | disodium sulfate | potassium nitrite | zinc carbonate
Substance properties
| potassium nitrate | soda ash | zinc sulfide | sodium sulfate | potassium nitrite | zinc carbonate molar mass | 101.1 g/mol | 105.99 g/mol | 97.44 g/mol | 142.04 g/mol | 85.103 g/mol | 125.4 g/mol phase | solid (at STP) | solid (at STP) | solid (at STP) | solid (at STP) | solid (at STP) | melting point | 334 °C | 851 °C | 1064 °C | 884 °C | 350 °C | boiling point | | 1600 °C | | 1429 °C | | density | | | 4.1 g/cm^3 | 2.68 g/cm^3 | 1.915 g/cm^3 | 4.3476 g/cm^3 solubility in water | soluble | soluble | | soluble | | insoluble dynamic viscosity | | 0.00355 Pa s (at 900 °C) | | | | odor | odorless | | | | |
Units