Input interpretation
Na_2CO_3 soda ash + Mg(NO_3)_2 magnesium nitrate ⟶ NaNO_3 sodium nitrate + MgCO_3 magnesium carbonate
Balanced equation
Balance the chemical equation algebraically: Na_2CO_3 + Mg(NO_3)_2 ⟶ NaNO_3 + MgCO_3 Add stoichiometric coefficients, c_i, to the reactants and products: c_1 Na_2CO_3 + c_2 Mg(NO_3)_2 ⟶ c_3 NaNO_3 + c_4 MgCO_3 Set the number of atoms in the reactants equal to the number of atoms in the products for C, Na, O, Mg and N: C: | c_1 = c_4 Na: | 2 c_1 = c_3 O: | 3 c_1 + 6 c_2 = 3 c_3 + 3 c_4 Mg: | c_2 = c_4 N: | 2 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_1 = 1 and solve the system of equations for the remaining coefficients: c_1 = 1 c_2 = 1 c_3 = 2 c_4 = 1 Substitute the coefficients into the chemical reaction to obtain the balanced equation: Answer: | | Na_2CO_3 + Mg(NO_3)_2 ⟶ 2 NaNO_3 + MgCO_3
Structures
+ ⟶ +
Names
soda ash + magnesium nitrate ⟶ sodium nitrate + magnesium carbonate
Equilibrium constant
Construct the equilibrium constant, K, expression for: Na_2CO_3 + Mg(NO_3)_2 ⟶ NaNO_3 + MgCO_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: Na_2CO_3 + Mg(NO_3)_2 ⟶ 2 NaNO_3 + MgCO_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 Na_2CO_3 | 1 | -1 Mg(NO_3)_2 | 1 | -1 NaNO_3 | 2 | 2 MgCO_3 | 1 | 1 Assemble the activity expressions accounting for the state of matter and ν_i: chemical species | c_i | ν_i | activity expression Na_2CO_3 | 1 | -1 | ([Na2CO3])^(-1) Mg(NO_3)_2 | 1 | -1 | ([Mg(NO3)2])^(-1) NaNO_3 | 2 | 2 | ([NaNO3])^2 MgCO_3 | 1 | 1 | [MgCO3] 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 = ([Na2CO3])^(-1) ([Mg(NO3)2])^(-1) ([NaNO3])^2 [MgCO3] = (([NaNO3])^2 [MgCO3])/([Na2CO3] [Mg(NO3)2])
Rate of reaction
Construct the rate of reaction expression for: Na_2CO_3 + Mg(NO_3)_2 ⟶ NaNO_3 + MgCO_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: Na_2CO_3 + Mg(NO_3)_2 ⟶ 2 NaNO_3 + MgCO_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 Na_2CO_3 | 1 | -1 Mg(NO_3)_2 | 1 | -1 NaNO_3 | 2 | 2 MgCO_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 Na_2CO_3 | 1 | -1 | -(Δ[Na2CO3])/(Δt) Mg(NO_3)_2 | 1 | -1 | -(Δ[Mg(NO3)2])/(Δt) NaNO_3 | 2 | 2 | 1/2 (Δ[NaNO3])/(Δt) MgCO_3 | 1 | 1 | (Δ[MgCO3])/(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[Na2CO3])/(Δt) = -(Δ[Mg(NO3)2])/(Δt) = 1/2 (Δ[NaNO3])/(Δt) = (Δ[MgCO3])/(Δt) (assuming constant volume and no accumulation of intermediates or side products)
Chemical names and formulas
| soda ash | magnesium nitrate | sodium nitrate | magnesium carbonate formula | Na_2CO_3 | Mg(NO_3)_2 | NaNO_3 | MgCO_3 Hill formula | CNa_2O_3 | MgN_2O_6 | NNaO_3 | CMgO_3 name | soda ash | magnesium nitrate | sodium nitrate | magnesium carbonate IUPAC name | disodium carbonate | magnesium dinitrate | sodium nitrate | magnesium carbonate
Substance properties
| soda ash | magnesium nitrate | sodium nitrate | magnesium carbonate molar mass | 105.99 g/mol | 148.31 g/mol | 84.994 g/mol | 84.313 g/mol phase | solid (at STP) | solid (at STP) | solid (at STP) | melting point | 851 °C | 88.9 °C | 306 °C | boiling point | 1600 °C | 330 °C | | density | | 1.2051 g/cm^3 | 2.26 g/cm^3 | solubility in water | soluble | | soluble | dynamic viscosity | 0.00355 Pa s (at 900 °C) | | 0.003 Pa s (at 250 °C) |
Units