Question

During a chemical change, substances react in characteristic ways to form new substances with different physical and chemical properties. Examples of chemical changes include burning of wood, cooking of an egg, rusting of iron, and souring of milk. You may have noticed another chemical change. Over time, some pennies change color from copper to green. This color change happens because of a chemical change. The copper metal that makes up a penny combines with:

A) Oxygen in the air
B) Carbon dioxide in the air
C) Water from the environment
D) All of the above

Answer 1

The green color change in pennies is a chemical change resulting from the reaction of copper with oxygen in the air, carbon dioxide, and water, making the correct answer D) All of the above.

Step-by-step explanation:

When a penny turns green over time, this color change is due to a chemical change involving the copper metal of the penny reacting with substances in its environment. Specifically, the copper combines with oxygen in the air, carbon dioxide, and water from the environment to form a new substance known as patina, which consists primarily of copper carbonate. This process is known as corrosion and is similar to rusting, in which iron reacts with oxygen and water to form rust. Therefore, the correct answer is D) All of the above.