I DON’T KNOW MUCH ABOUT IT.BUT A COMPOUND WITH A CHARGE ON IT IS DEFINITELY PLANAR.
I THINK IT IS SOMEWHAT HELPFUL FOR U.
THANK U
BYE.
						

							
HYBRIDISATION IS THE ONE OF THE PARAMETERS TO SAY THE PLANARITY OF A MOLECULE.BUT IT ALONE CAN’T SAY THE PLANARITY.PLANARITY OF A MOLECULE ALSO DEPENDS ON  THE ATOMS THAT IS ATTACHED TO THAT MOLECULE AND THE REFERENCE THROUGH WHICH WE ARE LOOKING.
						

							By the side of hybridisation, planarity comes for sp2 ans sp hybridisation, always. Aromatic compounds are always planer. And by the shape and geometry of the compund also palys an important rple in determining the planarity of the compund. Steric effect is another factor (repulsion between bulky groups present close to each other due to interaction of their electron cloud)  which leads to the deplanarity f a compund even it is aromatic.
						

							
In a structure of cyclopentene ,there is only one doubly bonded carbon atom so it is definately a alicyclic compound where as for any compound to be aromatic there is nessesory condition 1.cyclic system having conjugation of double bond and single bond in a compound
						

							
In geometry, coplanar refers to objects lying in the same plane. Coplanar would mean two substituents lying in the same plane. That is, both are wedged or dashed or in the plane of the paper (sticks). For example, if you want to do E2, you would need the leaving group (ex: tosylate) and the nucleophile (ex: hydroxide) to be in the same plane and anti at the same time due to transition state energy and steric hindrance effects.