Tennessee Wastewater Operator Practice Exam

What laboratory process involves adding a metal to a sample and boiling it to collect condensation?

1. Fractional distillation

2. Preliminary distillation

3. Simple distillation

4. Vacuum distillation

The correct answer is: Preliminary distillation

The process of adding a metal to a sample and boiling it to collect condensation is typically associated with preliminary distillation. Preliminary distillation is often used to remove impurities and separate components from a liquid mixture based on their boiling points. This step is essential in preparing a sample for further analysis or processing. In this process, the incorporation of a metal can aid in the boiling and condensation phases, improving separation efficiency and promoting the condensation of the desired components. The boiling action ensures that volatile substances vaporize and can then be condensed back into liquid form, allowing for the collection of the purified product. It's important to understand that while other distillation methods like simple, fractional, or vacuum distillation are related processes, they serve specific functions. Simple distillation is typically used for separating liquids with significantly different boiling points, fractional distillation is designed for mixtures with closer boiling points, and vacuum distillation is used for heat-sensitive materials by lowering the pressure to reduce boiling points. However, preliminary distillation's focus on initial purification through boiling and condensation is what makes it the most relevant choice for this question.