Answer:
The reactants in this chemical reaction are copper and oxygen, and the indicators of the chemical reaction include a change in color, release of energy in the form of heat, consumption of gas (oxygen), and a change in physical properties.
Step-by-step explanation:
The reactants in this chemical reaction are copper and oxygen. When copper reacts with oxygen in the air, it forms a new green substance called copper oxide (CuO).
There are several indicators of a chemical reaction that can be observed during this process. The first indicator is a change in color. In this case, the copper metal changes from its original reddish-brown color to a greenish-blue color as it reacts with oxygen to form copper oxide. This change in color is due to the formation of a new substance with different properties than the original reactants.
Another indicator of a chemical reaction is the release or absorption of energy in the form of heat, light, or sound. In this case, the reaction between copper and oxygen is exothermic, meaning that it releases heat energy. This can be observed by feeling the warmth produced by the reaction.
A third indicator of a chemical reaction is the formation of a precipitate or gas. In this case, no precipitate is formed, but a gas (oxygen) is consumed during the reaction.
Finally, a chemical reaction often involves a change in physical properties such as density, melting point, or boiling point. In this case, copper oxide has different physical properties than copper metal, such as being less dense and having a higher melting point.
In summary, the reactants in this chemical reaction are copper and oxygen, and the indicators of the chemical reaction include a change in color, release of energy in the form of heat, consumption of gas (oxygen), and a change in physical properties.