Respuesta :
Answer:
B. PCl₅ → PCl₃ + Cl₂.
Explanation:
- The conservation of mass is a phenomena that is applicable and found in chemical reaction but only balance chemical reactions.
- Balanced chemical reaction means that: The number of atoms of the reactants = the number of atoms in the products.
- In balanced chemical reaction; the atoms that enter and participate in the reaction will result from it and maintain the mass of each atom.
- The first choice (A) is wrong that it is unbalanced chemical reaction,
H₂O → H₂ + O₂, the oxygen has 1 atom in the reactants side while has 2 atoms in the products side.
to be balanced and apply conservation of the mass it should be: H₂O → H₂ + 1/2O₂.
- The second choice (B) is the right answer: PCl₅ → PCl₃ + Cl₂.
The number of atoms of P (1 atom) and Cl (5 atoms) are the same in both sides of reactants and products.
- The third choice (C) is wrong that it is unbalanced chemical reaction,
Na + Cl₂ → NaCl, the Cl has 2 atoms in the in the reactants side while has 1 atom in the products side.
to be balanced and apply conservation of the mass it should be: Na + 1/2Cl₂ → NaCl.
- The fourth choice (D) is wrong that it is unbalanced chemical reaction,
Al + Br₂ → AlBr₃, the Br has 2 atoms in the in the reactants side while has 3 atoms in the products side.
to be balanced and apply conservation of the mass it should be: 2Al + 3Br₂ → 2AlBr₃.