HCl + KNO3 = HNO3 + KCl

HCl hydrogen chloride + KNO_3 potassium nitrate ⟶ HNO_3 nitric acid + KCl potassium chloride

Balance the chemical equation algebraically: HCl + KNO_3 ⟶ HNO_3 + KCl Add stoichiometric coefficients, c_i, to the reactants and products: c_1 HCl + c_2 KNO_3 ⟶ c_3 HNO_3 + c_4 KCl Set the number of atoms in the reactants equal to the number of atoms in the products for Cl, H, K, N and O: Cl: | c_1 = c_4 H: | c_1 = c_3 K: | c_2 = c_4 N: | c_2 = c_3 O: | 3 c_2 = 3 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 = 1 Substitute the coefficients into the chemical reaction to obtain the balanced equation: Answer: | | HCl + KNO_3 ⟶ HNO_3 + KCl

+ ⟶ +

hydrogen chloride + potassium nitrate ⟶ nitric acid + potassium chloride

| hydrogen chloride | potassium nitrate | nitric acid | potassium chloride molecular free energy | -95.3 kJ/mol | -394.9 kJ/mol | -80.7 kJ/mol | -408.5 kJ/mol total free energy | -95.3 kJ/mol | -394.9 kJ/mol | -80.7 kJ/mol | -408.5 kJ/mol | G_initial = -490.2 kJ/mol | | G_final = -489.2 kJ/mol | ΔG_rxn^0 | -489.2 kJ/mol - -490.2 kJ/mol = 1 kJ/mol (endergonic) | | |

Construct the equilibrium constant, K, expression for: HCl + KNO_3 ⟶ HNO_3 + KCl 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: HCl + KNO_3 ⟶ HNO_3 + KCl 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 HCl | 1 | -1 KNO_3 | 1 | -1 HNO_3 | 1 | 1 KCl | 1 | 1 Assemble the activity expressions accounting for the state of matter and ν_i: chemical species | c_i | ν_i | activity expression HCl | 1 | -1 | ([HCl])^(-1) KNO_3 | 1 | -1 | ([KNO3])^(-1) HNO_3 | 1 | 1 | [HNO3] KCl | 1 | 1 | [KCl] 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 = ([HCl])^(-1) ([KNO3])^(-1) [HNO3] [KCl] = ([HNO3] [KCl])/([HCl] [KNO3])

Construct the rate of reaction expression for: HCl + KNO_3 ⟶ HNO_3 + KCl 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: HCl + KNO_3 ⟶ HNO_3 + KCl 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 HCl | 1 | -1 KNO_3 | 1 | -1 HNO_3 | 1 | 1 KCl | 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 HCl | 1 | -1 | -(Δ[HCl])/(Δt) KNO_3 | 1 | -1 | -(Δ[KNO3])/(Δt) HNO_3 | 1 | 1 | (Δ[HNO3])/(Δt) KCl | 1 | 1 | (Δ[KCl])/(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[HCl])/(Δt) = -(Δ[KNO3])/(Δt) = (Δ[HNO3])/(Δt) = (Δ[KCl])/(Δt) (assuming constant volume and no accumulation of intermediates or side products)

| hydrogen chloride | potassium nitrate | nitric acid | potassium chloride formula | HCl | KNO_3 | HNO_3 | KCl Hill formula | ClH | KNO_3 | HNO_3 | ClK name | hydrogen chloride | potassium nitrate | nitric acid | potassium chloride

| hydrogen chloride | potassium nitrate | nitric acid | potassium chloride molar mass | 36.46 g/mol | 101.1 g/mol | 63.012 g/mol | 74.55 g/mol phase | gas (at STP) | solid (at STP) | liquid (at STP) | solid (at STP) melting point | -114.17 °C | 334 °C | -41.6 °C | 770 °C boiling point | -85 °C | | 83 °C | 1420 °C density | 0.00149 g/cm^3 (at 25 °C) | | 1.5129 g/cm^3 | 1.98 g/cm^3 solubility in water | miscible | soluble | miscible | soluble dynamic viscosity | | | 7.6×10^-4 Pa s (at 25 °C) | odor | | odorless | | odorless