Final answer:
In chemistry, cis and trans configurations are used to describe different arrangements of atoms around a double bond. Cis isomers have the higher ranked molecules on the same side, while trans isomers have them on opposite sides. This affects the shape and properties of the molecule.
Step-by-step explanation:
In chemistry, the terms cis and trans are used to describe different arrangements of atoms around a double bond. When the higher ranked molecules are on the same side of the double bond, it is called the cis configuration. On the other hand, when the higher ranked molecules are on the opposite sides of the double bond, it is called the trans configuration.
For example, in the molecule butene (C4H8), if the two methyl groups are on the same side of the double bond, it is in the cis configuration. If the two methyl groups are on opposite sides of the double bond, it is in the trans configuration. The cis configuration causes a bend in the carbon backbone, while the trans configuration results in a more linear structure.