Why is the reaction of methane with oxygen classified as a chemical change?

• A. Because the physical state of methane changes from gas to liquid.
• B. Because the reaction only involves a change in temperature, not in chemical composition.
• C. Because new substances, such as carbon dioxide and water, are formed during the reaction.
• D. Because methane and oxygen are simply mixed together without forming new products.

Answer: (C)

Verified step by step guidance

1. Understand that a chemical change involves the formation of new substances with different chemical properties and compositions from the original substances.
2. Recognize that in the reaction of methane (CH\_4) with oxygen (O\_2), the reactants undergo a chemical transformation to produce new substances, specifically carbon dioxide (CO\_2) and water (H\_2O).
3. Note that this reaction is a combustion reaction, where methane reacts with oxygen to release energy and form new chemical products, indicating a change in chemical composition.
4. Contrast this with physical changes, which involve changes in physical state or temperature but do not produce new substances or alter chemical identities.
5. Conclude that the reaction is classified as a chemical change because new substances are formed, not merely because of changes in physical state or temperature.