Answer: Substance 3 is liquid at room temperature
Explanation: The common room temperature is assumed to be 20-22°C, we need to find the substance that will be in liquid state in that temperature.
For Substance 1, the boiling point is -195.975°C, and hence at room temperature, it would be in vapor phase and all liquid would have turned to gas.
For Substance 2, the boiling point is 3.85°C, and hence at room temperature, it would be in vapor phase and all liquid would have turned to gas in this case too.
For Substance 3, the boiling point is 77.85°C, and melting point is -108.15°C, hence at room temperature, it would be in liquid state.
For Substance 4, the melting point itself is 1800°C, due to which at room temperature it would be in solid state.