Final answer:
To test the hypothesis that solubility of sugar in water decreases with temperature, the independent variable is the temperature of water and the dependent variable is the solubility of sugar. This corresponds to option D. A solubility curve can be used to plot the experiment's results.
Step-by-step explanation:
To test the hypothesis that the solubility of sugar in water decreases as the temperature decreases, you would need to measure how much sugar can dissolve in water at various temperatures. The independent variable (IV) is the factor that you change deliberately during an experiment to see if it has an effect, which in this case is the temperature of water. The dependent variable (DV) is what you measure or observe to obtain your results, which would be the solubility of sugar. Thus, in this hypothetical experiment, the correct pairing of variables is Option D: IV- temperature of water, DV- Solubility of sugar.
During such an experiment, you would make a saturated sugar solution at different temperatures and measure the maximum amount of sugar that could be dissolved at those temperatures. This is typically done by adding sugar to water until no more can be dissolved (the point of saturation). The results could be plotted on a solubility curve, with temperature on the x-axis and solubility on the y-axis, allowing for visualization of the relationship between temperature and solubility.