Which observation most likely indicates that only a chemical change has taken place? (1 point)
O The change cannot be reversed.
O States of matter changes.
The shape changes.
OA reaction occurs.
G
A reaction occurs.
The observation that most likely indicates that only a chemical change has taken place is: A reaction occurs.
The observation that most likely indicates that only a chemical change has taken place is when a reaction occurs. To determine this, you need to understand the difference between a physical change and a chemical change.
A physical change is a change in the state, form, or appearance of a substance, without altering its chemical composition. Examples of physical changes include changes in state (e.g., melting ice), changes in shape (e.g., bending a paperclip), or changes in size (e.g., cutting a piece of paper).
On the other hand, a chemical change is a change that results in the formation of new substances with different chemical properties. Chemical changes involve the breaking and forming of chemical bonds. Examples of chemical changes include burning wood, rusting of iron, or digesting food.
In the given options, the observation that most likely indicates a chemical change is when a reaction occurs. A reaction occurring suggests that a chemical change has taken place, as new substances are being formed with different chemical properties.
Therefore, the correct answer is: A reaction occurs.