Which of the following best explains how melting ice differs from burning a substance?

• A. Burning is a physical change, while melting ice is a chemical change.
• B. Melting ice is a physical change because it does not alter the chemical composition of water, while burning is a chemical change that produces new substances.
• C. Melting ice and burning both involve the formation of new chemical compounds.
• D. Both melting ice and burning are physical changes because they only change the state of matter.

Answer: (B)

Verified step by step guidance

1. Understand the difference between physical and chemical changes: A physical change affects the form or state of a substance without changing its chemical composition, while a chemical change results in the formation of new substances with different chemical properties.
2. Analyze melting ice: When ice melts, it changes from solid to liquid water. This process involves a change in physical state but the chemical formula H\_2O remains the same, indicating no new substances are formed.
3. Analyze burning a substance: Burning (combustion) involves a chemical reaction where the original substance reacts with oxygen, producing new substances such as carbon dioxide, water vapor, or ash, which have different chemical compositions.
4. Compare the two processes: Melting ice is a physical change because it only changes the state of water without altering its chemical identity, whereas burning is a chemical change because it transforms the original substance into new chemical products.
5. Conclude which explanation is correct: The best explanation is that melting ice is a physical change and burning is a chemical change, as this distinction is based on whether the chemical composition changes or not.