Suppose that following a lava flow, pine grass (a hypothetical species) is the first species to colonize the area. Chemicals produced by pine grass change the soil chemistry in the environment, but these chemicals have little or no effect on subsequent colonization by later species. Which model would best explain this scenario of succession?

All the elements are arranged by melting points on the periodic table. in row they go from metals to gasses. in the row from sodium to argon, sodium is more reactive than the one on its right, magnesium.

You would be correct, boiling water does disinfect contamination.    the property of disinfecting means to kill  germs, bacteria and other pathogens or contamination  that might cause an infection or cause a person to become sickly. a couple methods of disinfecting are using soap, other cleaning supplies or by simply "boiling" the contaminate.  the reason why boiling water disinfects certain attributes is because some cells cannot survive the heat and pressure.