NaOH + CaO = NaO + CaOH

NaOH sodium hydroxide + CaO lime ⟶ NaO + CaOH

Balance the chemical equation algebraically: NaOH + CaO ⟶ NaO + CaOH Add stoichiometric coefficients, c_i, to the reactants and products: c_1 NaOH + c_2 CaO ⟶ c_3 NaO + c_4 CaOH Set the number of atoms in the reactants equal to the number of atoms in the products for H, Na, O and Ca: H: | c_1 = c_4 Na: | c_1 = c_3 O: | c_1 + c_2 = c_3 + c_4 Ca: | c_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: | | NaOH + CaO ⟶ NaO + CaOH

+ ⟶ NaO + CaOH

sodium hydroxide + lime ⟶ NaO + CaOH

Construct the equilibrium constant, K, expression for: NaOH + CaO ⟶ NaO + CaOH 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: NaOH + CaO ⟶ NaO + CaOH 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 NaOH | 1 | -1 CaO | 1 | -1 NaO | 1 | 1 CaOH | 1 | 1 Assemble the activity expressions accounting for the state of matter and ν_i: chemical species | c_i | ν_i | activity expression NaOH | 1 | -1 | ([NaOH])^(-1) CaO | 1 | -1 | ([CaO])^(-1) NaO | 1 | 1 | [NaO] CaOH | 1 | 1 | [CaOH] 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 = ([NaOH])^(-1) ([CaO])^(-1) [NaO] [CaOH] = ([NaO] [CaOH])/([NaOH] [CaO])

Construct the rate of reaction expression for: NaOH + CaO ⟶ NaO + CaOH 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: NaOH + CaO ⟶ NaO + CaOH 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 NaOH | 1 | -1 CaO | 1 | -1 NaO | 1 | 1 CaOH | 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 NaOH | 1 | -1 | -(Δ[NaOH])/(Δt) CaO | 1 | -1 | -(Δ[CaO])/(Δt) NaO | 1 | 1 | (Δ[NaO])/(Δt) CaOH | 1 | 1 | (Δ[CaOH])/(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[NaOH])/(Δt) = -(Δ[CaO])/(Δt) = (Δ[NaO])/(Δt) = (Δ[CaOH])/(Δt) (assuming constant volume and no accumulation of intermediates or side products)

| sodium hydroxide | lime | NaO | CaOH formula | NaOH | CaO | NaO | CaOH Hill formula | HNaO | CaO | NaO | HCaO name | sodium hydroxide | lime | |

| sodium hydroxide | lime | NaO | CaOH molar mass | 39.997 g/mol | 56.077 g/mol | 38.989 g/mol | 57.085 g/mol phase | solid (at STP) | solid (at STP) | | melting point | 323 °C | 2580 °C | | boiling point | 1390 °C | 2850 °C | | density | 2.13 g/cm^3 | 3.3 g/cm^3 | | solubility in water | soluble | reacts | | surface tension | 0.07435 N/m | | | dynamic viscosity | 0.004 Pa s (at 350 °C) | | |