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:

Boiling salt - water causes the water to evaporate as steam, leaving the salt behind. Freezing separates substances based on different freezing - points which is not applicable here. Chromatography separates mixtures based on their affinity for a stationary and mobile phase, not for salt - water separation. Sorting is used for separating solid objects by physical characteristics, not for separating a dissolved substance from a liquid.

Answer:

boiling