At room temperature, O2 is in gaseous state.
a gas has no definite volume or definite shape. It occupies volume of container and attains shape of container only.
Thus
It has no definite volume and takes the shape of its container.
Its particles move fast enough to overcome the attraction between them.: the gas molecules have minimum intermolecular interactions and have high kinetic energy.
It has more energy than it would at a cooler temperature: the kinetic energy of gas molecules increases with increase in temperature. Thus the energy increases with temperature and decreases with decrease in temperature.
