North Carolina Building Contractor License Practice Exam

Which components are used to make concrete?

1. Steel, sand, and water

2. Portland cement, fine aggregate, coarse aggregate, and water

3. Clay and water

4. Asphalt and water

The correct answer is: Portland cement, fine aggregate, coarse aggregate, and water

Concrete is primarily composed of four main components: Portland cement, fine aggregate (usually sand), coarse aggregate (such as gravel or crushed stone), and water. Portland cement acts as the binding agent, providing the strength and durability needed for the concrete mixture once it hydrates. Fine aggregate and coarse aggregate together contribute to the overall structure and volume, ensuring that concrete has the appropriate consistency and strength characteristics based on the intended use. Water is crucial as it initiates the chemical reaction with cement, a process called hydration, which is essential for the concrete to harden and gain strength. This composition makes option B the correct choice, as it captures the essential materials needed to produce concrete effectively and highlights the importance of each component in the mixing process. Other options listed do not include the proper combination or are entirely based on different materials that are not used in concrete production.