In what ways are the roots of a plant like an ion-exchanger used to purify hard water?
A) The roots release ions, which exchange with the mineral ions in the soil.
B) The plant roots purify water.
C) The plant roots trap ions in the water and store them until recharged.
D) all of the above
E) none of the above
Question 2
Many solvents expand to occupy greater volumes with increasing temperature. What happens to the concentration of a solution made with such a solvent as its temperature is increased?
A) Since concentration depends on how much mass is dissolved in a given volume, as the volume increases, the concentration decreases.
B) The concentration of a solution increases as the solute fits into the new spaces between the molecules.
C) Since it has a greater ability to dissolve more solute at a higher temperature, its concentration has decreased.
D) Since it has a greater ability to dissolve more solute at a higher temperature, its concentration has increased.
