Cl2 + P = PCl3

chlorine + red phosphorus ⟶ phosphorus trichloride

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

+ ⟶

chlorine + red phosphorus ⟶ phosphorus trichloride

| chlorine | red phosphorus | phosphorus trichloride Hill formula | Cl_2 | P | Cl_3P name | chlorine | red phosphorus | phosphorus trichloride IUPAC name | molecular chlorine | phosphorus | trichlorophosphane

| chlorine | red phosphorus | phosphorus trichloride molar mass | 70.9 g/mol | 30.973761998 g/mol | 137.3 g/mol phase | gas (at STP) | solid (at STP) | liquid (at STP) melting point | -101 °C | 579.2 °C | -112 °C boiling point | -34 °C | | 76 °C density | 0.003214 g/cm^3 (at 0 °C) | 2.16 g/cm^3 | 1.574 g/cm^3 solubility in water | | insoluble | decomposes surface tension | | | 0.0291 N/m dynamic viscosity | | 7.6×10^-4 Pa s (at 20.2 °C) | 5.29×10^-4 Pa s (at 25 °C)