Question

which observation most likely indicates that only a chemical change has taken place?(1 point) states of matter changes. states of matter changes. the change cannot be reversed. the change cannot be reversed. a reaction occurs. a reaction occurs. the shape changes. the shape changes.

Answer 1

An observation that indicates a change cannot be easily reversed, such as a color change, temperature variation, light emission, bubble formation (not from boiling), or precipitate formation, suggests that a chemical change has occurred.

Step-by-step explanation:

An observation that most likely indicates that only a chemical change has taken place is one where the change cannot be easily reversed. This is supported by the fact that chemical changes are typically harder to reverse than physical changes. For example, if a substance undergoes a color change, has a temperature change, emits light, forms bubbles (not caused by boiling), or results in the formation of a precipitate, these are all hallmark signs of a chemical reaction. These observations suggest that the original substances’ molecular structure has been altered, resulting in new substances with different properties.