Input interpretation
H_2SO_4 sulfuric acid + NaNO_2 sodium nitrite ⟶ Na_2SO_4 sodium sulfate + HNO_2 nitrous acid
Balanced equation
Balance the chemical equation algebraically: H_2SO_4 + NaNO_2 ⟶ Na_2SO_4 + HNO_2 Add stoichiometric coefficients, c_i, to the reactants and products: c_1 H_2SO_4 + c_2 NaNO_2 ⟶ c_3 Na_2SO_4 + c_4 HNO_2 Set the number of atoms in the reactants equal to the number of atoms in the products for H, O, S, N and Na: H: | 2 c_1 = c_4 O: | 4 c_1 + 2 c_2 = 4 c_3 + 2 c_4 S: | c_1 = c_3 N: | c_2 = c_4 Na: | c_2 = 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 = 2 c_3 = 1 c_4 = 2 Substitute the coefficients into the chemical reaction to obtain the balanced equation: Answer: | | H_2SO_4 + 2 NaNO_2 ⟶ Na_2SO_4 + 2 HNO_2
Structures
+ ⟶ +
Names
sulfuric acid + sodium nitrite ⟶ sodium sulfate + nitrous acid
Equilibrium constant
Construct the equilibrium constant, K, expression for: H_2SO_4 + NaNO_2 ⟶ Na_2SO_4 + HNO_2 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: H_2SO_4 + 2 NaNO_2 ⟶ Na_2SO_4 + 2 HNO_2 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_2SO_4 | 1 | -1 NaNO_2 | 2 | -2 Na_2SO_4 | 1 | 1 HNO_2 | 2 | 2 Assemble the activity expressions accounting for the state of matter and ν_i: chemical species | c_i | ν_i | activity expression H_2SO_4 | 1 | -1 | ([H2SO4])^(-1) NaNO_2 | 2 | -2 | ([NaNO2])^(-2) Na_2SO_4 | 1 | 1 | [Na2SO4] HNO_2 | 2 | 2 | ([HNO2])^2 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 = ([H2SO4])^(-1) ([NaNO2])^(-2) [Na2SO4] ([HNO2])^2 = ([Na2SO4] ([HNO2])^2)/([H2SO4] ([NaNO2])^2)
Rate of reaction
Construct the rate of reaction expression for: H_2SO_4 + NaNO_2 ⟶ Na_2SO_4 + HNO_2 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: H_2SO_4 + 2 NaNO_2 ⟶ Na_2SO_4 + 2 HNO_2 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_2SO_4 | 1 | -1 NaNO_2 | 2 | -2 Na_2SO_4 | 1 | 1 HNO_2 | 2 | 2 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_2SO_4 | 1 | -1 | -(Δ[H2SO4])/(Δt) NaNO_2 | 2 | -2 | -1/2 (Δ[NaNO2])/(Δt) Na_2SO_4 | 1 | 1 | (Δ[Na2SO4])/(Δt) HNO_2 | 2 | 2 | 1/2 (Δ[HNO2])/(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[H2SO4])/(Δt) = -1/2 (Δ[NaNO2])/(Δt) = (Δ[Na2SO4])/(Δt) = 1/2 (Δ[HNO2])/(Δt) (assuming constant volume and no accumulation of intermediates or side products)
Chemical names and formulas
| sulfuric acid | sodium nitrite | sodium sulfate | nitrous acid formula | H_2SO_4 | NaNO_2 | Na_2SO_4 | HNO_2 Hill formula | H_2O_4S | NNaO_2 | Na_2O_4S | HNO_2 name | sulfuric acid | sodium nitrite | sodium sulfate | nitrous acid IUPAC name | sulfuric acid | sodium nitrite | disodium sulfate | nitrous acid
Substance properties
| sulfuric acid | sodium nitrite | sodium sulfate | nitrous acid molar mass | 98.07 g/mol | 68.995 g/mol | 142.04 g/mol | 47.013 g/mol phase | liquid (at STP) | solid (at STP) | solid (at STP) | melting point | 10.371 °C | 271 °C | 884 °C | boiling point | 279.6 °C | | 1429 °C | density | 1.8305 g/cm^3 | 2.168 g/cm^3 | 2.68 g/cm^3 | solubility in water | very soluble | | soluble | surface tension | 0.0735 N/m | | | dynamic viscosity | 0.021 Pa s (at 25 °C) | | | odor | odorless | | |
Units