Question

1. which of the following is not a sign that a chemical reaction may have occurred? a. sudden color change from clear to yellow b. changing state from liquid to gas c. the formation of a precipitate d. giving off heat 17. four different liquids (syrup, water, motor oil, and alcohol) are spilled at the

Explanation:

A change of state from liquid to gas is a physical change (evaporation), not a definite sign of a chemical reaction. Chemical reactions are characterized by the formation of new substances, which can be indicated by color - change, precipitate - formation, or heat - evolution.

Answer:

B. Changing state from liquid to gas