The describe geometry of the substance fits that of a linear molecule with two domains.
This description is based on the VSEPR i.e Valence Shell Electron Pair repulsion(VSEPR) model. It states that if an atom is bonded by two or more kinds of atoms the shape is determined by the geometry of the bonds around the central atom.
The electron domain is the number of lone pairs of electron around an atom.
Here in CO₂:
there are two lone pairs and the oxygen atoms are in a 180° linear shape around the central carbon atom. The bond is made up of two O⇔C structure.
an increase in temperature will lead to an increase in effective collision which also result in an increase in volume, when the temperature decreases, the volume will decrease
