Question

The nodal plane in the pi bond of ethene is located in the molecular plane

Answer 1

Formation of a ππ-bond occurs by the sideways overlap of p-orbitals of two C-atoms.The molecular plane does not have any π-electron density since the p-orbitals are perpendicular to the plane containing the ethene molecule.The nodal plane in the π-bond of ethene is located in the molecular plane.

So yes you are correct

Answer 2

The nodal plane is always present between the lobes of pi orbitals
In case of ethene the two lobes are located above and below the plane as shown in the figure .
So clearly we can see that the nodal plane is located on the molecular plane....
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