H2SO4 + KClO3 + C12H22O11 = H2O + CO2 + SO2 + KCl

H_2SO_4 sulfuric acid + KClO_3 potassium chlorate + C_12H_22O_11 sucrose ⟶ H_2O water + CO_2 carbon dioxide + SO_2 sulfur dioxide + KCl potassium chloride

Balance the chemical equation algebraically: H_2SO_4 + KClO_3 + C_12H_22O_11 ⟶ H_2O + CO_2 + SO_2 + KCl Add stoichiometric coefficients, c_i, to the reactants and products: c_1 H_2SO_4 + c_2 KClO_3 + c_3 C_12H_22O_11 ⟶ c_4 H_2O + c_5 CO_2 + c_6 SO_2 + c_7 KCl Set the number of atoms in the reactants equal to the number of atoms in the products for H, O, S, Cl, K and C: H: | 2 c_1 + 22 c_3 = 2 c_4 O: | 4 c_1 + 3 c_2 + 11 c_3 = c_4 + 2 c_5 + 2 c_6 S: | c_1 = c_6 Cl: | c_2 = c_7 K: | c_2 = c_7 C: | 12 c_3 = 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_3 = 1 and solve the system of equations for the remaining coefficients: c_2 = 8 - c_1/3 c_3 = 1 c_4 = c_1 + 11 c_5 = 12 c_6 = c_1 c_7 = 8 - c_1/3 The resulting system of equations is still underdetermined, so an additional coefficient must be set arbitrarily. Set c_1 = 12 and solve for the remaining coefficients: c_1 = 12 c_2 = 4 c_3 = 1 c_4 = 23 c_5 = 12 c_6 = 12 c_7 = 4 Substitute the coefficients into the chemical reaction to obtain the balanced equation: Answer: | | 12 H_2SO_4 + 4 KClO_3 + C_12H_22O_11 ⟶ 23 H_2O + 12 CO_2 + 12 SO_2 + 4 KCl

+ + ⟶ + + +

sulfuric acid + potassium chlorate + sucrose ⟶ water + carbon dioxide + sulfur dioxide + potassium chloride

| sulfuric acid | potassium chlorate | sucrose | water | carbon dioxide | sulfur dioxide | potassium chloride molecular enthalpy | -814 kJ/mol | -397.7 kJ/mol | -2226 kJ/mol | -285.8 kJ/mol | -393.5 kJ/mol | -296.8 kJ/mol | -436.5 kJ/mol total enthalpy | -9768 kJ/mol | -1591 kJ/mol | -2226 kJ/mol | -6574 kJ/mol | -4722 kJ/mol | -3562 kJ/mol | -1746 kJ/mol | H_initial = -13585 kJ/mol | | | H_final = -16604 kJ/mol | | | ΔH_rxn^0 | -16604 kJ/mol - -13585 kJ/mol = -3019 kJ/mol (exothermic) | | | | | |

Construct the equilibrium constant, K, expression for: H_2SO_4 + KClO_3 + C_12H_22O_11 ⟶ H_2O + CO_2 + SO_2 + 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: 12 H_2SO_4 + 4 KClO_3 + C_12H_22O_11 ⟶ 23 H_2O + 12 CO_2 + 12 SO_2 + 4 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 H_2SO_4 | 12 | -12 KClO_3 | 4 | -4 C_12H_22O_11 | 1 | -1 H_2O | 23 | 23 CO_2 | 12 | 12 SO_2 | 12 | 12 KCl | 4 | 4 Assemble the activity expressions accounting for the state of matter and ν_i: chemical species | c_i | ν_i | activity expression H_2SO_4 | 12 | -12 | ([H2SO4])^(-12) KClO_3 | 4 | -4 | ([KClO3])^(-4) C_12H_22O_11 | 1 | -1 | ([C12H22O11])^(-1) H_2O | 23 | 23 | ([H2O])^23 CO_2 | 12 | 12 | ([CO2])^12 SO_2 | 12 | 12 | ([SO2])^12 KCl | 4 | 4 | ([KCl])^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 = ([H2SO4])^(-12) ([KClO3])^(-4) ([C12H22O11])^(-1) ([H2O])^23 ([CO2])^12 ([SO2])^12 ([KCl])^4 = (([H2O])^23 ([CO2])^12 ([SO2])^12 ([KCl])^4)/(([H2SO4])^12 ([KClO3])^4 [C12H22O11])

Construct the rate of reaction expression for: H_2SO_4 + KClO_3 + C_12H_22O_11 ⟶ H_2O + CO_2 + SO_2 + 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: 12 H_2SO_4 + 4 KClO_3 + C_12H_22O_11 ⟶ 23 H_2O + 12 CO_2 + 12 SO_2 + 4 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 H_2SO_4 | 12 | -12 KClO_3 | 4 | -4 C_12H_22O_11 | 1 | -1 H_2O | 23 | 23 CO_2 | 12 | 12 SO_2 | 12 | 12 KCl | 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_2SO_4 | 12 | -12 | -1/12 (Δ[H2SO4])/(Δt) KClO_3 | 4 | -4 | -1/4 (Δ[KClO3])/(Δt) C_12H_22O_11 | 1 | -1 | -(Δ[C12H22O11])/(Δt) H_2O | 23 | 23 | 1/23 (Δ[H2O])/(Δt) CO_2 | 12 | 12 | 1/12 (Δ[CO2])/(Δt) SO_2 | 12 | 12 | 1/12 (Δ[SO2])/(Δt) KCl | 4 | 4 | 1/4 (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 = -1/12 (Δ[H2SO4])/(Δt) = -1/4 (Δ[KClO3])/(Δt) = -(Δ[C12H22O11])/(Δt) = 1/23 (Δ[H2O])/(Δt) = 1/12 (Δ[CO2])/(Δt) = 1/12 (Δ[SO2])/(Δt) = 1/4 (Δ[KCl])/(Δt) (assuming constant volume and no accumulation of intermediates or side products)

| sulfuric acid | potassium chlorate | sucrose | water | carbon dioxide | sulfur dioxide | potassium chloride formula | H_2SO_4 | KClO_3 | C_12H_22O_11 | H_2O | CO_2 | SO_2 | KCl Hill formula | H_2O_4S | ClKO_3 | C_12H_22O_11 | H_2O | CO_2 | O_2S | ClK name | sulfuric acid | potassium chlorate | sucrose | water | carbon dioxide | sulfur dioxide | potassium chloride IUPAC name | sulfuric acid | potassium chlorate | (2R, 3S, 4S, 5S, 6R)-2-[(2S, 3S, 4S, 5R)-3, 4-dihydroxy-2, 5-bis(hydroxymethyl)oxolan-2-yl]oxy-6-(hydroxymethyl)oxane-3, 4, 5-triol | water | carbon dioxide | sulfur dioxide | potassium chloride