Al + S8 = Al2S3

Al (aluminum) + S_8 (rhombic sulfur) ⟶ Al_2S_3 (aluminum sulfide)

Balance the chemical equation algebraically: Al + S_8 ⟶ Al_2S_3 Add stoichiometric coefficients, c_i, to the reactants and products: c_1 Al + c_2 S_8 ⟶ c_3 Al_2S_3 Set the number of atoms in the reactants equal to the number of atoms in the products for Al and S: Al: | c_1 = 2 c_3 S: | 8 c_2 = 3 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_2 = 1 and solve the system of equations for the remaining coefficients: c_1 = 16/3 c_2 = 1 c_3 = 8/3 Multiply by the least common denominator, 3, to eliminate fractional coefficients: c_1 = 16 c_2 = 3 c_3 = 8 Substitute the coefficients into the chemical reaction to obtain the balanced equation: Answer: | | 16 Al + 3 S_8 ⟶ 8 Al_2S_3

+ ⟶

aluminum + rhombic sulfur ⟶ aluminum sulfide

| aluminum | rhombic sulfur | aluminum sulfide molecular enthalpy | 0 kJ/mol | 0 kJ/mol | -724 kJ/mol total enthalpy | 0 kJ/mol | 0 kJ/mol | -5792 kJ/mol | H_initial = 0 kJ/mol | | H_final = -5792 kJ/mol ΔH_rxn^0 | -5792 kJ/mol - 0 kJ/mol = -5792 kJ/mol (exothermic) | |

K_c = [Al2S3]^8/([Al]^16 [S8]^3)

rate = -1/16 (Δ[Al])/(Δt) = -1/3 (Δ[S8])/(Δt) = 1/8 (Δ[Al2S3])/(Δt) (assuming constant volume and no accumulation of intermediates or side products)

| aluminum | rhombic sulfur | aluminum sulfide formula | Al | S_8 | Al_2S_3 name | aluminum | rhombic sulfur | aluminum sulfide IUPAC name | aluminum | octathiocane | thioxo-(thioxoalumanylthio)alumane

| aluminum | rhombic sulfur | aluminum sulfide molar mass | 26.9815385 g/mol | 256.5 g/mol | 150.1 g/mol phase | solid (at STP) | solid (at STP) | solid (at STP) melting point | 660.4 °C | | 1100 °C boiling point | 2460 °C | | 1500 °C density | 2.7 g/cm^3 | 2.07 g/cm^3 | 2.02 g/cm^3 solubility in water | insoluble | | decomposes surface tension | 0.817 N/m | | dynamic viscosity | 1.5×10^-4 Pa s (at 760 °C) | | odor | odorless | |