Input interpretation
H_2O water + KOH potassium hydroxide + Zn zinc + KNO_3 potassium nitrate ⟶ NH_3 ammonia + K2Zn(OH)4
Balanced equation
Balance the chemical equation algebraically: H_2O + KOH + Zn + KNO_3 ⟶ NH_3 + K2Zn(OH)4 Add stoichiometric coefficients, c_i, to the reactants and products: c_1 H_2O + c_2 KOH + c_3 Zn + c_4 KNO_3 ⟶ c_5 NH_3 + c_6 K2Zn(OH)4 Set the number of atoms in the reactants equal to the number of atoms in the products for H, O, K, Zn and N: H: | 2 c_1 + c_2 = 3 c_5 + 4 c_6 O: | c_1 + c_2 + 3 c_4 = 4 c_6 K: | c_2 + c_4 = 2 c_6 Zn: | c_3 = c_6 N: | c_4 = c_5 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_4 = 1 and solve the system of equations for the remaining coefficients: c_1 = 6 c_2 = 7 c_3 = 4 c_4 = 1 c_5 = 1 c_6 = 4 Substitute the coefficients into the chemical reaction to obtain the balanced equation: Answer: | | 6 H_2O + 7 KOH + 4 Zn + KNO_3 ⟶ NH_3 + 4 K2Zn(OH)4
Structures
+ + + ⟶ + K2Zn(OH)4
Names
water + potassium hydroxide + zinc + potassium nitrate ⟶ ammonia + K2Zn(OH)4
Equilibrium constant
Construct the equilibrium constant, K, expression for: H_2O + KOH + Zn + KNO_3 ⟶ NH_3 + K2Zn(OH)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: 6 H_2O + 7 KOH + 4 Zn + KNO_3 ⟶ NH_3 + 4 K2Zn(OH)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 H_2O | 6 | -6 KOH | 7 | -7 Zn | 4 | -4 KNO_3 | 1 | -1 NH_3 | 1 | 1 K2Zn(OH)4 | 4 | 4 Assemble the activity expressions accounting for the state of matter and ν_i: chemical species | c_i | ν_i | activity expression H_2O | 6 | -6 | ([H2O])^(-6) KOH | 7 | -7 | ([KOH])^(-7) Zn | 4 | -4 | ([Zn])^(-4) KNO_3 | 1 | -1 | ([KNO3])^(-1) NH_3 | 1 | 1 | [NH3] K2Zn(OH)4 | 4 | 4 | ([K2Zn(OH)4])^4 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 = ([H2O])^(-6) ([KOH])^(-7) ([Zn])^(-4) ([KNO3])^(-1) [NH3] ([K2Zn(OH)4])^4 = ([NH3] ([K2Zn(OH)4])^4)/(([H2O])^6 ([KOH])^7 ([Zn])^4 [KNO3])
Rate of reaction
Construct the rate of reaction expression for: H_2O + KOH + Zn + KNO_3 ⟶ NH_3 + K2Zn(OH)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: 6 H_2O + 7 KOH + 4 Zn + KNO_3 ⟶ NH_3 + 4 K2Zn(OH)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 H_2O | 6 | -6 KOH | 7 | -7 Zn | 4 | -4 KNO_3 | 1 | -1 NH_3 | 1 | 1 K2Zn(OH)4 | 4 | 4 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 H_2O | 6 | -6 | -1/6 (Δ[H2O])/(Δt) KOH | 7 | -7 | -1/7 (Δ[KOH])/(Δt) Zn | 4 | -4 | -1/4 (Δ[Zn])/(Δt) KNO_3 | 1 | -1 | -(Δ[KNO3])/(Δt) NH_3 | 1 | 1 | (Δ[NH3])/(Δt) K2Zn(OH)4 | 4 | 4 | 1/4 (Δ[K2Zn(OH)4])/(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 = -1/6 (Δ[H2O])/(Δt) = -1/7 (Δ[KOH])/(Δt) = -1/4 (Δ[Zn])/(Δt) = -(Δ[KNO3])/(Δt) = (Δ[NH3])/(Δt) = 1/4 (Δ[K2Zn(OH)4])/(Δt) (assuming constant volume and no accumulation of intermediates or side products)
Chemical names and formulas
| water | potassium hydroxide | zinc | potassium nitrate | ammonia | K2Zn(OH)4 formula | H_2O | KOH | Zn | KNO_3 | NH_3 | K2Zn(OH)4 Hill formula | H_2O | HKO | Zn | KNO_3 | H_3N | H4K2O4Zn name | water | potassium hydroxide | zinc | potassium nitrate | ammonia |
Substance properties
| water | potassium hydroxide | zinc | potassium nitrate | ammonia | K2Zn(OH)4 molar mass | 18.015 g/mol | 56.105 g/mol | 65.38 g/mol | 101.1 g/mol | 17.031 g/mol | 211.6 g/mol phase | liquid (at STP) | solid (at STP) | solid (at STP) | solid (at STP) | gas (at STP) | melting point | 0 °C | 406 °C | 420 °C | 334 °C | -77.73 °C | boiling point | 99.9839 °C | 1327 °C | 907 °C | | -33.33 °C | density | 1 g/cm^3 | 2.044 g/cm^3 | 7.14 g/cm^3 | | 6.96×10^-4 g/cm^3 (at 25 °C) | solubility in water | | soluble | insoluble | soluble | | surface tension | 0.0728 N/m | | | | 0.0234 N/m | dynamic viscosity | 8.9×10^-4 Pa s (at 25 °C) | 0.001 Pa s (at 550 °C) | | | 1.009×10^-5 Pa s (at 25 °C) | odor | odorless | | odorless | odorless | |
Units