Question

If you aren't sure if a chemical reaction has occurred, look for evidence in the properties of the products. When a new substance forms, its properties will be different from the properties of the reactants. You might notice a change in color, smell or temperature. But be careful because some physical changes can look a lot like chemical reactions. A change of

state--like from a solid to a gas--is not a chemical reaction. And a color change alone is not enough to know if a chemical reaction has taken place. The main purpose of this passage is to:

A) Describe different physical properties of substances and how they can be observed.
B) Describe what evidence can be used to determine if a reaction has taken place.

Answer 1

To determine if a chemical reaction has occurred, one should look for evidence of change in the properties of the products, such as color, smell, temperature, or the formation of bubbles or a precipitate.

Step-by-step explanation:

A chemical reaction can be identified by observing certain evidence in the properties of the products. One should look for changes in color, smell, temperature, the formation of bubbles, or the formation of a precipitate. However, it is important to note that some physical changes can mimic chemical reactions, so a change in state or color alone is not enough to determine if a chemical reaction has occurred.