Final answer:
Matchbooks composed of paper are unlikely to spontaneously ignite due to age, as combustion requires an external heat source that surpasses the high activation energy needed for paper to burn.
Step-by-step explanation:
The concern about the combustibility of paper in your collection of matchbooks can be addressed through understanding the chemistry of combustion. Paper is a combustible material, but ignition is not a spontaneous event at room temperature. This is due to the fact that the activation energy for paper to combust is too high for the ambient conditions. The collisions between oxygen molecules and the paper under normal conditions are not sufficient to start a fire.
However, when a match is struck and the flame heats the paper, it reaches a temperature where the molecules have enough energy to react. This reaction is exothermic, releasing heat that then sustains the reaction, allowing the paper to continue burning. The matchbooks you have collected are unlikely to ignite due to age, as long as they are not exposed to an external flame or significant heat source.