Elemental phosphorus exists as molecules of P4. It reacts with Cl2(g) to produce phosphorus pentachloride.Write the balanced chemical equation for this reaction.

Verified step by step guidance

1. Identify the reactants and products in the chemical reaction. The reactants are P4 and Cl2, and the product is phosphorus pentachloride, which is PCl5.
2. Write the unbalanced chemical equation using the chemical formulas: P4 + Cl2 -> PCl5.
3. Balance the phosphorus atoms first. Since there are 4 phosphorus atoms in P4, you need 4 PCl5 molecules to balance the phosphorus: P4 + Cl2 -> 4 PCl5.
4. Next, balance the chlorine atoms. Each PCl5 molecule contains 5 chlorine atoms, so 4 PCl5 molecules contain 20 chlorine atoms. Therefore, you need 10 Cl2 molecules to provide 20 chlorine atoms: P4 + 10 Cl2 -> 4 PCl5.
5. Verify that the equation is balanced by counting the atoms of each element on both sides of the equation. There should be 4 phosphorus atoms and 20 chlorine atoms on each side.

Key Concepts

Molecular Formulas

Molecular formulas represent the number and types of atoms in a molecule. For phosphorus, the molecular formula P4 indicates that each molecule consists of four phosphorus atoms. Understanding molecular formulas is essential for writing balanced chemical equations, as they provide the necessary information about the reactants and products involved in a chemical reaction.

Balancing Chemical Equations

Balancing chemical equations involves ensuring that the number of atoms for each element is the same on both the reactant and product sides. This is based on the law of conservation of mass, which states that matter cannot be created or destroyed in a chemical reaction. To balance an equation, coefficients are adjusted in front of the chemical formulas to achieve equal atom counts.

Chemical Reactions and Products

In a chemical reaction, reactants undergo a transformation to form products. In this case, phosphorus (P4) reacts with chlorine gas (Cl2) to produce phosphorus pentachloride (PCl5). Understanding the nature of reactants and products is crucial for predicting the outcome of a reaction and for writing the correct balanced equation.