Question

the passage below describes an experiment. bradley filled 12 identical bottles with the same volume of distilled water. he kept 4 bottles of distilled water, added one teaspoon of epsom salt to each of the next 4 bottles, and added two teaspoons of epsom salt to each of the remaining 4 bottles. he added a drop of soap to the first bottle and shook it to make bubbles. he then used a ruler to measure the thickness of the bubble layer. once he had repeated the procedure with all the bottles, bradley calculated the average thickness of the bubble layer for each set of 4 and compared them. identify the question that the experiment can best answer. does soap produce a thicker bubble layer in pure water than it does in sugar water? do soap bubbles pop more easily in pure water than in salty water? does the amount of epsom salt dissolved in water affect the thickness of the bubble layer when soap is added?

Explanation:

Bradley's experiment involves different amounts of Epsom salt (independent variable) and measures the bubble - layer thickness (dependent variable). The first option mentions sugar water (not in the experiment), and the second option is about bubbles popping (not measured in the experiment). The third option aligns with the variables in the experiment (amount of Epsom salt and bubble - layer thickness).

Answer:

Does the amount of Epsom salt dissolved in water affect the thickness of the bubble layer when soap is added?