C2H2O2 = COH2OC

OHCCHO glyoxal ⟶ OHCCHO glyoxal

Balance the chemical equation algebraically: OHCCHO ⟶ OHCCHO Add stoichiometric coefficients, c_i, to the reactants and products: c_1 OHCCHO ⟶ c_2 OHCCHO Set the number of atoms in the reactants equal to the number of atoms in the products for C, H and O: C: | 2 c_1 = 2 c_2 H: | 2 c_1 = 2 c_2 O: | 2 c_1 = 2 c_2 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 Substitute the coefficients into the chemical reaction to obtain the balanced equation: Answer: | | OHCCHO ⟶ OHCCHO

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glyoxal ⟶ glyoxal

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

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

| glyoxal | glyoxal formula | OHCCHO | OHCCHO Hill formula | C_2H_2O_2 | C_2H_2O_2 name | glyoxal | glyoxal IUPAC name | oxaldehyde | oxaldehyde

| glyoxal | glyoxal molar mass | 58.036 g/mol | 58.036 g/mol phase | liquid (at STP) | liquid (at STP) boiling point | 51 °C | 51 °C density | 1.265 g/cm^3 | 1.265 g/cm^3