The correct option for separating a solid dissolved in a liquid solution is **A. Filtration**. ### Detailed Explanation **1. Understanding Filtration:** Filtration is a physical separation process that is used to separate solids from liquids or gases using a filter medium that allows only the fluid to pass through while retaining the solid particles. The filter can be made of various materials, such as paper, cloth, or specialized membranes, depending on the size of the particles being separated. **How Filtration Works:** - When a mixture of solid and liquid is poured through a filter, the solid particles are trapped on the filter paper, while the liquid (filtrate) passes through. - The size of the pores in the filter determines what can pass through and what gets trapped. For example, a coffee filter can separate coffee grounds from brewed coffee. **2. Why Filtration is the Best Option:** - **Direct Separation:** Filtration directly separates solids from liquids without altering the chemical composition of either component. - **Simplicity:** It is a straightforward and commonly used method that requires minimal equipment. - **Effectiveness:** It is effective for suspensions where solid particles are not dissolved but are dispersed in the liquid. ### Analysis of Other Options **B. Centrifugation:** - **What it is:** Centrifugation involves spinning a mixture at high speeds to create a force that separates components based on their density. - **Why it’s weaker:** While centrifugation can separate solids from liquids, it is more suitable for suspensions where the solid particles are not dissolved but rather are larger and denser. If the solid is truly dissolved (like salt in water), centrifugation will not effectively separate it. **C. Distillation:** - **What it is:** Distillation is a separation technique that relies on differences in boiling points to separate components of a liquid mixture. - **Why it’s weaker:** Distillation is not suitable for separating solids from liquids. It is primarily used for separating liquid mixtures or purifying liquids. If a solid is dissolved in a liquid, distillation would not isolate the solid; instead, it would vaporize the liquid and leave the solid behind, but this is not the intended separation of a dissolved solid. **D. Chromatography:** - **What it is:** 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. - **Why it’s weaker:** Chromatography is typically used for separating mixtures of compounds, especially in analytical chemistry. It is not the best choice for separating a solid that is dissolved in a liquid, as it is more complex and requires specific conditions to separate different substances based on their affinities. ### Summary of Key Points - **Filtration** is the best method for separating a solid from a liquid solution because it directly captures solid particles while allowing the liquid to pass through. - **Centrifugation** is effective for suspensions but not for dissolved solids. - **Distillation** is used for separating liquids based on boiling points, not for solids in solutions. - **Chromatography** is more complex and suited for separating mixtures of compounds rather than solid-liquid separations. ### Revision Summary - Filtration is the most effective method for separating solids from liquids. - It works by trapping solid particles on a filter while allowing the liquid to pass through. - Other methods like centrifugation, distillation, and chromatography are less suitable for this specific task. - Understanding the properties of the mixture is crucial for selecting the appropriate separation technique.