Final answer:
The balanced chemical equation for P4 + Cl2 → PCl5 is P4 + 10 Cl2 → 4 PCl5, using the smallest whole number coefficients to ensure an equal number of each type of atom on both sides.
Step-by-step explanation:
To balance the chemical equation P4 + Cl2 → PCl5, we need to ensure that there are equal numbers of each type of atom on both sides of the equation. This involves placing coefficients in front of the chemical formulas to achieve this balance.
The balanced chemical reaction is: P4 + 10 Cl2 → 4 PCl5. Here, we have 4 phosphorus atoms on both sides and 20 chlorine atoms on both sides, balancing the equation with the smallest whole number coefficients and maintaining the law of conservation of mass.