HAZMAT Technician Practice Exam

What is a solution?

1. A solid material mixed with another solid

2. A uniform mixture formed when a solute is dissolved in a solvent

3. A gas dissolved in another gas

4. A purely liquid substance

The correct answer is: A uniform mixture formed when a solute is dissolved in a solvent

A solution is best defined as a uniform mixture that occurs when a solute is fully dissolved in a solvent. When you think about solutions, you can consider how substances interact at the molecular level. In a solution, the solute—often a solid, liquid, or gas—integrates with the solvent, which is usually a liquid, to create a homogenous mixture. In this context, the term "uniform mixture" is particularly important because it implies that the composition is consistent throughout; every part of the solution has the same concentration of the solute. This property distinguishes solutions from other types of mixtures, like suspensions or colloids, where the components may not be evenly distributed. For instance, when sugar (the solute) is dissolved in water (the solvent), the individual sugar molecules disperse evenly throughout the water, resulting in a solution that appears the same throughout, no matter where it is sampled. This concept does not apply to the other choices, as they either describe different types of mixtures (such as the combination of two solids or gases) or miss the essential aspect of homogeneity that characterizes a solution. This understanding of solutions is crucial for anyone involved in HAZMAT operations, as knowing how substances mix can affect handling