The phosphorus and sulfur on the tip of the match are burned up during the chemical reaction and create light and heat energy. There are 3 other pieces of evidence that prove a chemical change or chemical reaction has taken place. The 3 rdexample is called a precipitate. When two liquid are combined together, but a solid is produced that solid is called a precipitate. The 4 thpiece of evidence is an unexpected temperature change. Often heat is released when elements or compounds are combined. This change is temperature proves a chemical reaction occurred. Lastly, sometimes an unexpected color change occurs when two chemicals are combined. This is evidence of a chemical change. Rust is one example of an unexpected chemical change. 3. List the 5 pieces of evidence that prove a chemical change or chemical reaction has occurred.

Answer 1

The five pieces of evidence that prove a chemical change or chemical reaction has occurred are:

1. Release of Light and Heat: Energy is released in the form of light and heat, indicating that a chemical reaction has taken place.

2. Formation of a Precipitate: When two liquids are combined and a solid is produced, that solid is known as a precipitate, indicating a chemical change.

3. Unexpected Temperature Change: A noticeable change in temperature, whether heat is released (exothermic reaction) or absorbed (endothermic reaction), suggests a chemical reaction has occurred.

4. Unexpected Color Change: A change in color when two substances are mixed can indicate a chemical reaction, as the formation of new substances may involve the emergence of different colors.

5. Production of Gas: The formation of bubbles or the release of gas during the reaction signifies a chemical change has taken place as new gaseous substances are produced.

These indicators help in identifying that a chemical reaction has occurred, transforming the initial substances into new products.