**Correct Option: A. Filtration** ### Detailed Explanation: **1. Understanding the Techniques:** - **Filtration:** This technique involves passing a mixture through a filter paper or a porous material that allows the liquid to pass through while retaining the solid particles. It is commonly used to separate solids from liquids in heterogeneous mixtures. - **Distillation:** This method is used to separate components of a liquid mixture based on differences in boiling points. It is not suitable for isolating solids from liquids. - **Chromatography:** This technique separates components of a mixture based on their different affinities to a stationary phase and a mobile phase. It is primarily used for separating and analyzing mixtures of chemicals, not for isolating solids from liquids. - **Centrifugation:** This method uses centrifugal force to separate components of a mixture based on their density. It is effective for separating solids from liquids but is more commonly used for suspensions and emulsions. **2. Why Filtration is the Best Choice:** - When you have a solid solute dissolved in a liquid solution, filtration is the most straightforward and effective method to isolate the solid. The filter paper acts as a barrier that allows the liquid (the filtrate) to pass through while trapping the solid particles (the residue). - For example, if you have a mixture of sand and water, pouring the mixture through filter paper will allow the water to pass through while the sand remains on the paper. This is a direct application of filtration. **3. Why the Other Options are Incorrect:** - **B. Distillation:** This method is not suitable for isolating solids from liquids because it relies on the vaporization of liquids. If the solid is dissolved in the liquid, distillation would not effectively separate the solid; instead, it would separate the liquid components based on their boiling points. - **C. Chromatography:** While chromatography is excellent for separating different substances in a mixture, it is not designed for isolating a solid from a liquid. It is more complex and requires specific conditions to separate components based on their chemical properties. - **D. Centrifugation:** Although centrifugation can separate solids from liquids, it is typically used for suspensions where the solid particles are not completely dissolved. In cases where the solid is dissolved, centrifugation would not be effective, as the solid would remain in the solution. ### Example Calculation: While there are no calculations needed for this question, it is important to understand the practical application of filtration. If you were to filter a solution, you would set up your apparatus as follows: - Place a funnel in a stand. - Insert filter paper into the funnel. - Pour the mixture into the funnel. - Collect the liquid that passes through in a clean container. ### Common Pitfalls: - Confusing filtration with other separation techniques like distillation or chromatography. Remember that filtration is specifically for separating solids from liquids. - Assuming that centrifugation can always be used to separate solids from liquids; it is not effective for dissolved solids. ### Revision Summary: - **Filtration** is the best method for isolating solid solutes from liquid solutions. - **Distillation** separates liquids based on boiling points, not suitable for solids. - **Chromatography** is for separating components based on chemical properties, not for solid-liquid separation. - **Centrifugation** is effective for suspensions but not for dissolved solids.