Answer: The statement which could possibly not be true is C -" Liquid X can exist as a stable phase at 25°C, 1atm."
Explanation:
Triple point is the point where a substance co-exist as solid liquid and gas. At any point other than the triple point, the substance exist as a single phase substance.
As shown in the diagram, Liquid cannot exist as a stable phase at 1atm( below the the triple point pressure of 2atm) as the liquid can only exist beyond the pressure of triple point.
In gases the only thing that isn't related is acidity.
animals, grass, and decomposers
Hydrogen
Hydrogen is identified by the glowing splint described in the question.