Which of the following statements best describes the reversibility of chemical changes?

• A. Chemical changes are reversible in all cases, similar to physical changes.
• B. Chemical changes are reversible only if energy is not involved.
• C. Chemical changes are generally irreversible because they result in the formation of new substances.
• D. Chemical changes are always easily reversible and do not produce new substances.

Answer: (C)

Verified step by step guidance

1. Understand the definition of a chemical change: it involves the formation of new substances with different properties from the original substances.
2. Recognize that reversibility refers to whether a process can be undone to restore the original substances.
3. Recall that physical changes (like melting or freezing) are often reversible because they do not change the chemical identity of the substance.
4. Note that chemical changes usually involve breaking and forming chemical bonds, which often makes the process difficult or impossible to reverse under normal conditions.
5. Conclude that chemical changes are generally irreversible because they produce new substances, distinguishing them from physical changes.