Question

why is boiling point of liquid above room temperature whereas boiling point of gas is below room temperature

Answer 1

If the melting point of a substance is below the room temperature,then its physical state at normal room temperature i.e. 25 degree celcius is liquid state.If its boiling point is below the room temperature then its physical state is gas. 
Take for example water.its melting point(0 degree celcius).so at room temperature it is a liquid.but iron's melting point is above room temperature. so it is a solid.similarly oxygen is a gas at room temperature coz its melting as well as boiling point is below room temperature.


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