Cis and trans isomers are positional isomers of a molecule. Consider something such as PtCl2Br2 which is a square planar complex Pt sits in the middle with each of the ligands (in this case the...
Actually, the cis isomer has a higher boiling point than the trans one because cis isomers are polar and therefore it requires of more heat to break the stronger intermolecular force
This is a single bonded compound and cis-trans isomerism is only possible when fre rotation about a bond is restricted or a double bond or cycle is essential for existence of cis-trans isomers.
Trans isomers pack together better so the Van der Waals forces (intermolecular forces) between the isomers are stronger than in cis isomers; thus, the melting point of trans isomers is higher.