Answer
The state of a substance depends upon its temperature and inter-molecular forces.
Work Step by Step
Gasses have the weakest inter-molecular forces. Substances with moderate inter-molecular forces are liquid at room temperature. Substances with strong inter-molecular forces are solid at room temperature.
At lower temperature most of the substances are solid. At moderate temperature most of the substances are liquids and at higher temperature they turn into the gaseous state, for they have enough energy to break the inter-molecular attractions.
