Answer:
The substance can be best classified as a molecular substance
Step-by-step explanation:
The given information are;
The physical state of the substance at 25°C = Solid state
The physical state of the substance at 150°C = Molten
Molecular substances are those with bonds formed by electron sharing among the constituent atoms and they contain a few number of atoms per molecule. Molecular compounds with molecular weight less than 100, usually exist as liquids or gases at room temperature, while those with molecular weights over 100 can be found in a solid state at room temperature.
Generally, molecular compounds are usually volatile and have a melting point less than 300°C
Therefore, the substance can be best classified as a molecular substance.