What is an alloy?

• A. A mixture of water and salt.
• B. A substance formed by combining two or more elements, usually metals, to improve properties.
• C. A pure metal.
• D. A compound consisting of carbon.

Answer: (B)

An alloy is a substance formed by combining two or more elements, usually metals, to improve properties. This is why metals like steel, brass, and bronze are valued: mixing elements changes characteristics such as strength, hardness, or durability. For example, iron with carbon produces steel, which is stronger than pure iron, while copper with zinc makes brass, and copper with tin makes bronze.

Mixing water and salt is a simple mixture or solution, not an alloy, because it isn’t a solid material built from a metal lattice. A pure metal isn’t an alloy, since it’s just one element. A compound consisting of carbon describes chemical compounds, not an alloy. Alloys involve combining elements to form a material with properties different from the individual elements.