Final answer:
Increasing sugar concentration in water creates a hypertonic solution that causes water to move out of potato cubes via osmosis, leading to a loss in mass of the potato cubes.
Step-by-step explanation:
Increasing the concentration of sugar in water can affect the mass of potato cubes through a process known as osmosis. Osmosis is the movement of water across a semipermeable membrane from an area of low solute concentration (hypotonic) to an area of high solute concentration (hypertonic). When potato cubes are placed in a hypertonic solution, which is what happens when you increase the sugar concentration, water from inside the potato cells is drawn out into the surrounding environment to try to balance the solute concentrations. This results in the potato cubes losing mass as their water content decreases.
For example, if you have a glass of water with a single teaspoon of sugar (hypotonic solution) and another glass with a quarter cup of sugar (hypertonic solution), and you place potato cubes in both glasses, the cubes in the hypertonic solution will lose mass. The reason for this is the sugar concentration acts to draw water out of the potato cells due to the osmotic pressure difference between the inside of the cells and the surrounding sugary water.