In the reaction of magnesium metal with hydrochloric acid, how do you determine when the magnesium metal has reacted completely? a. All of the water has evaporated.
b. The magnesium metal is gone.
c. The dilute HCl is gone.
d. Gas bubbles are no longer produced.

What effect would average population growth have on land usage? a. urban use of land would rise to more than 30 percent of available land. b. industrial use of land would rise to more than 30 percent of available land. c. the percentage of available land used as cropland would stay the same. d. cropland would fall to about 10 percent of available land.