Standard Molar Volume is the volume occupied by one mole of any gas at STP. Remember that "STP" is Standard Temperature and Pressure. Standard temperature is 0 &176:C or 273 K. Standard pressure is 1 atmosphere or 760 mm Hg (also called "torr"). 1 mole of any gas at STP occupies 22.4 liters of volume.
The best option is melting point
A physical change.
Physical change = can be reverted + doesn't change substance
Chemical = changes substance