Final answer:
The best method to separate solid sugar from sugar water is by evaporation, where heating the solution allows the water to evaporate and the sugar to crystallize.
Step-by-step explanation:
To separate solid sugar from a sugar water solution, the most effective method would be evaporation. Since sugar does not evaporate, heating the solution will allow the water to evaporate, leaving the sugar behind. This process is essentially a physical separation technique that exploits the different boiling points of the substances involved. When sugar is dissolved in water, it creates a homogeneous mixture where the sugar molecules are dispersed evenly throughout the water.
Indeed, if such a solution were passed through a filter, both sugar and water would pass through since the sugar particles are extremely small (usually less than 1 nm in diameter) and do not get trapped by the filter. Therefore, filtration is not an effective method to separate sugar from water. Instead, by gently heating the solution, water turns into vapor, which can be collected by condensation if desired, and the sugar will crystallize as the water content decreases. This process is known as crystallization.