Question

which physical method can be used for obtaining a sample of salt from a small beaker of salt water?
boiling
freezing
chromatography
sorting

Explanation:

To obtain salt from salt water (a solution of salt and water), we can use the physical method of boiling. Boiling the salt water will cause the water to evaporate (turn into vapor), leaving the salt behind. Freezing would turn the salt water into ice, but the salt would not be separated effectively in a simple way. Chromatography is used for separating components of a mixture based on their different affinities for a stationary and mobile phase, which is not suitable for separating salt from water. Sorting is a method for separating different solid objects, not for separating a solute from a solvent in a solution.

Answer:

A. boiling