My question: Yes / no, is the following a verifiable fact?
"Moss growth is greatly impacted by the pH of the rock it grows on."
Please think gradually:

Show your work and conclude with the exact phrasing "Therefore, the final answer is [answer]." where [answer] is just the final number or expression that solves the problem.
user
Rock pH does not change so long as the rock stays in a solid state.
Thus, the answer is no.