Final answer:
The solution outside of the dialysis bag is best described as hypotonic, since it has a lower concentration of solutes compared to the sugar solution inside the bag.
Step-by-step explanation:
The best word to describe the solution outside of the bag when a scientist dissolves some sugar in a liter of water, places this solution into a dialysis bag, and then places the bag in a beaker of distilled water is hypotonic.
In biology, when comparing two solutions, the hypotonic solution has a lower concentration of solutes (such as sugar) than another solution. As the sugar solution inside the dialysis bag is compared to the distilled water outside, the distilled water is hypotonic because it contains a lower concentration of solutes. Therefore, water will tend to move into the dialysis bag, following its concentration gradient.
A hypertonic solution would have a higher concentration of solutes compared to another solution. The sugar solution inside the bag is hypertonic to the distilled water outside. An isotonic solution would have equal concentrations of solutes between the two solutions, leading to no net water movement. The term flaccid is not used to describe the relative tonicity of solutions.