An aqueous mixture containing starch (a colloid), NaCl, glucose, and albumin (a colloid) is placed in a dialyzing bag and immersed in distilled water. Which of the following correctly describes the location of the indicated substance after dialysis?

A-albumin, inside
B-starch outside
C-albumin inside and outside
D-water inside only
E-starch inside and outside

To determine the location of substances after dialysis, we need to understand the process of dialysis and the properties of the substances involved.

Dialysis is a process of separating solutes based on their size. It involves using a semi-permeable membrane, such as a dialyzing bag, which allows small solute molecules and solvent molecules to pass through, while retaining larger solute molecules. The process relies on the principle of diffusion, where solute molecules move from areas of high concentration to areas of low concentration.

In the given mixture, we have starch, NaCl, glucose, and albumin. Starch and albumin are colloids, which are large particles suspended in the solution. NaCl and glucose, on the other hand, are small solutes.

When the dialyzing bag is immersed in distilled water, the water molecules will move into the bag through the semi-permeable membrane via osmosis. This movement of water will cause a decrease in the concentration of solutes inside the bag.

Since albumin is a large solute molecule, it will be retained inside the bag as it cannot easily pass through the semi-permeable membrane. Therefore, option A ("albumin, inside") is correct.

Starch is also a large solute molecule, like albumin, and will not be able to pass through the semi-permeable membrane. Hence, it will stay outside the bag. Therefore, option B ("starch, outside") is correct.

NaCl and glucose are small solutes that can easily pass through the semi-permeable membrane. The presence of water from the outside will cause these solutes to diffuse out of the bag. Hence, they will be found both inside and outside the bag. Therefore, option C ("albumin, inside and outside") is correct.

Based on the explanations above, the correct answer is C - albumin inside and outside.