Passage IV
Companies W-Z were suspected of diluting pure (100%) honey before packaging it for sale. Students investigated each company's product by using the process of osmosis. During osmosis, H2O flows across a semipermeable membrane (such as dialysis tubing) from a solution having a lower solute concentration into one with a higher solute concentration. Smaller molecules (such as H2O) can pass through tiny pores in the dialysis tubing, but larger molecules (such as sugars) cannot.
Experiment 1
Two mL of 100% honey was mixed with 8 mL of H2O to form a 20% honey solution. A 40%, a 60%, and an 80% honey solution were also made. A sample of 1 of the 4 solutions, 100% honey, or pure H2O was added to each of 6 bags made of dialysis tubing. Air was pressed out of the bags, the bags were sealed, and the initial mass of each bag plus its contents was measured. Each bag was fully submerged in a separate beaker of pure H2O at 25°C for 2 hr. The bags were then removed and dried off, and the final mass of each bag plus its contents was measured (see Table 1).
Experiment 2
A sample of each company's product was added to a separate bag and tested as in Experiment 1 (see Table 2).
Experiment 3
A sample of Company Z's product was added to 5 bags. The samples were tested as in Experiment 1, except that the bags were submerged in separate beakers containing, respectively, 20%, 40%, 60%, 80%, or 100% honey. The mass of the bag plus its contents increased for 4 of the bags, but decreased for 1 of the bags.
16. Suppose that in Experiment 1 the students had also tested a 70% honey solution. Based on the results of Experiment 1, the percent change in mass would most likely have been between:
Your Answer is
Correct Answer is H
Explanation
70% is between 60%-80%, so find their corresponding percent change in mass values of 45 and 77 in table 1, so you should choose 45%-77%