Which statement best describes the equation CaCO3 + 2HCl → CaCl2 + CO2 + H2O?

• A. The equation is balanced because the number of atoms of each element is the same on both sides.
• B. The equation is not balanced because there are fewer oxygen atoms on the product side.
• C. The equation is not balanced because there are more chlorine atoms on the reactant side.
• D. The equation is not balanced because the number of hydrogen atoms is different on each side.

Answer: (A)

Verified step by step guidance

1. Identify all the elements involved in the reaction: calcium (Ca), carbon (C), oxygen (O), hydrogen (H), and chlorine (Cl).
2. Count the number of atoms of each element on the reactant side: Ca (1), C (1), O (3), H (2 from 2HCl), Cl (2 from 2HCl).
3. Count the number of atoms of each element on the product side: Ca (1 in CaCl2), C (1 in CO2), O (2 in CO2 + 1 in H2O = 3 total), H (2 in H2O), Cl (2 in CaCl2).
4. Compare the counts of each element on both sides to check if they are equal, which indicates the equation is balanced.
5. Conclude that since the number of atoms of each element is the same on both sides, the equation is balanced.