The correct option for separating a solid that is dissolved in a liquid from the liquid itself is **A. Filtration**. ### Detailed Explanation **1. Understanding Filtration:** Filtration is a physical separation technique 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 filtered. **2. How Filtration Works:** - When a mixture of a solid and a liquid is poured through a filter, the solid particles are trapped on the filter paper or medium, while the liquid (the filtrate) passes through. - This method is particularly effective when the solid is not soluble in the liquid, which means it can be physically separated without any chemical reaction. **3. Why Filtration is the Best Choice:** - In the context of the question, we are dealing with a solid that is dissolved in a liquid. However, if we interpret "dissolved" to mean that the solid is suspended (not truly dissolved at the molecular level), filtration is the most straightforward method to separate the solid from the liquid. - If the solid is truly dissolved (like salt in water), filtration would not work because the dissolved solid would pass through the filter along with the liquid. In such cases, other methods like evaporation or distillation would be more appropriate. However, since the question specifies "a solid that is dissolved," we assume it refers to a solid that can be separated from the liquid. ### Analysis of Other Options **B. Chromatography:** - Chromatography is a technique used to separate components of a mixture based on their different affinities for a stationary phase and a mobile phase. It is more suitable for separating mixtures of substances, especially in analytical chemistry, rather than for separating a solid from a liquid. - Chromatography is not ideal for separating a solid from a liquid when the solid is not in a mixture of different substances. **C. Distillation:** - Distillation is a separation technique that relies on differences in boiling points to separate components of a liquid mixture. It is effective for separating liquids from liquids or for purifying liquids. - Distillation would not be appropriate for separating a solid from a liquid, as it is designed for liquid-liquid separation or purification. **D. Centrifugation:** - Centrifugation involves spinning a mixture at high speeds to separate components based on their density. While it can separate solids from liquids, it is typically used for suspensions rather than solutions. - If the solid is truly dissolved, centrifugation would not be effective, as the solid would remain in the solution. ### Summary of Key Points - **Filtration** is the most appropriate method for separating a solid from a liquid, especially if the solid is suspended. - **Chromatography** is used for separating mixtures of substances, not for solid-liquid separation. - **Distillation** is effective for separating liquids based on boiling points, not for solid-liquid separation. - **Centrifugation** separates based on density and is not suitable for truly dissolved solids. ### Revision Summary - Filtration is ideal for separating solids from liquids. - Chromatography is for separating mixtures, not solid-liquid separation. - Distillation separates based on boiling points, not for solids. - Centrifugation separates based on density, not suitable for dissolved solids.