SiO2 + BrF3 = O2 + Br2 + SiF3

SiO_2 silicon dioxide + BrF_3 bromine trifluoride ⟶ O_2 oxygen + Br_2 bromine + SiF3

Balance the chemical equation algebraically: SiO_2 + BrF_3 ⟶ O_2 + Br_2 + SiF3 Add stoichiometric coefficients, c_i, to the reactants and products: c_1 SiO_2 + c_2 BrF_3 ⟶ c_3 O_2 + c_4 Br_2 + c_5 SiF3 Set the number of atoms in the reactants equal to the number of atoms in the products for O, Si, Br and F: O: | 2 c_1 = 2 c_3 Si: | c_1 = c_5 Br: | c_2 = 2 c_4 F: | 3 c_2 = 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_4 = 1 and solve the system of equations for the remaining coefficients: c_1 = 2 c_2 = 2 c_3 = 2 c_4 = 1 c_5 = 2 Substitute the coefficients into the chemical reaction to obtain the balanced equation: Answer: | | 2 SiO_2 + 2 BrF_3 ⟶ 2 O_2 + Br_2 + 2 SiF3

+ ⟶ + + SiF3

silicon dioxide + bromine trifluoride ⟶ oxygen + bromine + SiF3

Construct the equilibrium constant, K, expression for: SiO_2 + BrF_3 ⟶ O_2 + Br_2 + SiF3 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: 2 SiO_2 + 2 BrF_3 ⟶ 2 O_2 + Br_2 + 2 SiF3 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 SiO_2 | 2 | -2 BrF_3 | 2 | -2 O_2 | 2 | 2 Br_2 | 1 | 1 SiF3 | 2 | 2 Assemble the activity expressions accounting for the state of matter and ν_i: chemical species | c_i | ν_i | activity expression SiO_2 | 2 | -2 | ([SiO2])^(-2) BrF_3 | 2 | -2 | ([BrF3])^(-2) O_2 | 2 | 2 | ([O2])^2 Br_2 | 1 | 1 | [Br2] SiF3 | 2 | 2 | ([SiF3])^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 = ([SiO2])^(-2) ([BrF3])^(-2) ([O2])^2 [Br2] ([SiF3])^2 = (([O2])^2 [Br2] ([SiF3])^2)/(([SiO2])^2 ([BrF3])^2)

Construct the rate of reaction expression for: SiO_2 + BrF_3 ⟶ O_2 + Br_2 + SiF3 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: 2 SiO_2 + 2 BrF_3 ⟶ 2 O_2 + Br_2 + 2 SiF3 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 SiO_2 | 2 | -2 BrF_3 | 2 | -2 O_2 | 2 | 2 Br_2 | 1 | 1 SiF3 | 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 SiO_2 | 2 | -2 | -1/2 (Δ[SiO2])/(Δt) BrF_3 | 2 | -2 | -1/2 (Δ[BrF3])/(Δt) O_2 | 2 | 2 | 1/2 (Δ[O2])/(Δt) Br_2 | 1 | 1 | (Δ[Br2])/(Δt) SiF3 | 2 | 2 | 1/2 (Δ[SiF3])/(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 = -1/2 (Δ[SiO2])/(Δt) = -1/2 (Δ[BrF3])/(Δt) = 1/2 (Δ[O2])/(Δt) = (Δ[Br2])/(Δt) = 1/2 (Δ[SiF3])/(Δt) (assuming constant volume and no accumulation of intermediates or side products)

| silicon dioxide | bromine trifluoride | oxygen | bromine | SiF3 formula | SiO_2 | BrF_3 | O_2 | Br_2 | SiF3 Hill formula | O_2Si | BrF_3 | O_2 | Br_2 | F3Si name | silicon dioxide | bromine trifluoride | oxygen | bromine | IUPAC name | dioxosilane | | molecular oxygen | molecular bromine |

| silicon dioxide | bromine trifluoride | oxygen | bromine | SiF3 molar mass | 60.083 g/mol | 136.9 g/mol | 31.998 g/mol | 159.81 g/mol | 85.08 g/mol phase | solid (at STP) | liquid (at STP) | gas (at STP) | liquid (at STP) | melting point | 1713 °C | 8.77 °C | -218 °C | -7.2 °C | boiling point | 2950 °C | 125.8 °C | -183 °C | 58.8 °C | density | 2.196 g/cm^3 | 2.803 g/cm^3 | 0.001429 g/cm^3 (at 0 °C) | 3.119 g/cm^3 | solubility in water | insoluble | decomposes | | insoluble | surface tension | | 0.0363 N/m | 0.01347 N/m | 0.0409 N/m | dynamic viscosity | | | 2.055×10^-5 Pa s (at 25 °C) | 9.44×10^-4 Pa s (at 25 °C) | odor | odorless | | odorless | |