**Correct Option: A. Filtration** ### Explanation of Why Filtration is the Correct Answer Filtration is a separation technique that is specifically designed to separate solids from liquids in a heterogeneous mixture. In a heterogeneous mixture, the components are not uniformly distributed, and the solid particles can be distinguished from the liquid phase. **Step-by-Step Explanation:** 1. **Understanding Filtration:** - Filtration involves passing a mixture through a filter medium (like filter paper or a membrane) that allows the liquid to pass through while retaining the solid particles. - The filter paper has tiny pores that are small enough to trap solid particles but large enough to allow liquid molecules to pass through. 2. **Process of Filtration:** - When a heterogeneous mixture (e.g., sand and water) is poured through a filter, the solid (sand) is caught on the filter paper, while the liquid (water) passes through and is collected in a container below. - This process effectively separates the solid from the liquid, making it a straightforward and efficient method for this type of separation. 3. **Applications of Filtration:** - Filtration is commonly used in laboratories and industries to purify liquids, separate precipitates from solutions, and in water treatment processes to remove impurities. ### Why the Other Options are Incorrect or Weaker **B. Distillation:** - **Explanation:** Distillation is a technique used to separate components of a mixture based on differences in boiling points. It is effective for separating liquids from liquids (like alcohol from water) or for purifying liquids. - **Why It's Weaker:** Distillation is not suitable for separating solids from liquids because it relies on vaporization and condensation, which does not apply to solid particles suspended in a liquid. **C. Chromatography:** - **Explanation:** Chromatography is a technique used to separate components of a mixture based on their movement through a stationary phase while being carried by a mobile phase. It is often used for separating different substances in a solution. - **Why It's Weaker:** Chromatography is more complex and is typically used for separating small quantities of substances, such as pigments in ink or different compounds in a solution, rather than for separating solid particles from a liquid. **D. Evaporation:** - **Explanation:** Evaporation is the process of turning a liquid into vapor, which can be used to separate a dissolved solid from a liquid (like salt from saltwater). - **Why It's Weaker:** While evaporation can separate a solid from a liquid, it is not as direct or efficient as filtration for heterogeneous mixtures where the solid is not dissolved. Evaporation also requires the liquid to be heated, which may not be practical in all situations. ### Summary of Key Points - **Filtration** is the most effective method for separating solids from liquids in heterogeneous mixtures. - It works by using a filter medium to trap solid particles while allowing the liquid to pass through. - Other methods like distillation, chromatography, and evaporation are not suitable for this specific separation task. - Understanding the properties of the mixture and the separation techniques is crucial for selecting the appropriate method. This thorough understanding of filtration and its comparison with other methods will help you effectively tackle questions related to separation techniques in chemistry.