Answer:
C)We cannot be sure unless we find out its boiling point.
Explanation:
I will like to clearly state that simply comparing two compounds will not tell us exactly which one will be a liquid, solid or gas at room temperature.
If I want to determine whether an unknown substance will be a liquid at room temperature, I will have to measure its boiling point. If the boiling point is above room temperature, and the melting point is below room temperature, it’s a liquid. If the boiling point of the unknown substance is below room temperature, it is a gas.
This confirms that we cannot conclude on the state of matter in which a compound exists unless we know something about its boiling point, not by inspecting the properties of neighbouring compounds in the same homologous series
