Question

Hypothesis: If molecules are small enough, then they will diffuse across a semipermeable membrane because they can pass through its tiny openings. The independent variable in this experiment was ____, and the dependent variable was ____.

a) Temperature, diffusion rate
b) Molecule size, diffusion across the membrane
c) Time, membrane thickness
d) Concentration gradient, membrane color

Answer 1

The independent variable in this experiment was molecule size, and the dependent variable was diffusion across the membrane.

Step-by-step explanation:

The independent variable in this experiment was molecule size, and the dependent variable was diffusion across the membrane.

In diffusion, small molecules pass through a semipermeable membrane from an area of higher concentration to an area of lower concentration. The size of the molecules determines their ability to pass through the tiny openings in the membrane. Therefore, molecule size is the independent variable that was manipulated in the experiment, while diffusion across the membrane is the dependent variable that was measured and observed.