H2O + P + HClO3 = HCl + H3PO4

water + red phosphorus + HClO3 ⟶ hydrogen chloride + phosphoric acid

Balance the chemical equation algebraically: + + HClO3 ⟶ + Add stoichiometric coefficients, c_i, to the reactants and products: c_1 + c_2 + c_3 HClO3 ⟶ c_4 + c_5 Set the number of atoms in the reactants equal to the number of atoms in the products for H, O, P and Cl: H: | 2 c_1 + c_3 = c_4 + 3 c_5 O: | c_1 + 3 c_3 = 4 c_5 P: | c_2 = c_5 Cl: | c_3 = c_4 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_1 = 9/5 c_2 = 6/5 c_3 = 1 c_4 = 1 c_5 = 6/5 Multiply by the least common denominator, 5, to eliminate fractional coefficients: c_1 = 9 c_2 = 6 c_3 = 5 c_4 = 5 c_5 = 6 Substitute the coefficients into the chemical reaction to obtain the balanced equation: Answer: | | 9 + 6 + 5 HClO3 ⟶ 5 + 6

+ + HClO3 ⟶ +

water + red phosphorus + HClO3 ⟶ hydrogen chloride + phosphoric acid

| water | red phosphorus | HClO3 | hydrogen chloride | phosphoric acid formula | | | HClO3 | | Hill formula | H_2O | P | HClO3 | ClH | H_3O_4P name | water | red phosphorus | | hydrogen chloride | phosphoric acid IUPAC name | water | phosphorus | | hydrogen chloride | phosphoric acid

| water | red phosphorus | HClO3 | hydrogen chloride | phosphoric acid molar mass | 18.015 g/mol | 30.973761998 g/mol | 84.45 g/mol | 36.46 g/mol | 97.994 g/mol phase | liquid (at STP) | solid (at STP) | | gas (at STP) | liquid (at STP) melting point | 0 °C | 579.2 °C | | -114.17 °C | 42.4 °C boiling point | 99.9839 °C | | | -85 °C | 158 °C density | 1 g/cm^3 | 2.16 g/cm^3 | | 0.00149 g/cm^3 (at 25 °C) | 1.685 g/cm^3 solubility in water | | insoluble | | miscible | very soluble surface tension | 0.0728 N/m | | | | dynamic viscosity | 8.9×10^-4 Pa s (at 25 °C) | 7.6×10^-4 Pa s (at 20.2 °C) | | | odor | odorless | | | | odorless