American Chemical Society (ACS) Chemistry Practice Exam

The dx2-y2 orbital has a distinctive shape characterized by having four lobes that extend along the x and y axes. This orientation allows for the lobes to be positioned in the directions between the two axes, effectively creating a configuration that resembles a cloverleaf. The presence of four lobes indicates that this orbital is specifically designed to hold electrons in a manner that maximizes their distance from the nucleus while aligning with the geometrical axes of the coordinate system. In contrast, the other shapes mentioned in the options do not reflect the characteristics of the dx2-y2 orbital. A spherical shape would correspond to the s orbitals, which are uniform in all directions. A dumbbell shape is typical of p orbitals, which contain two distinct lobes but do not have the four-lobed characteristic of the dx2-y2 orbital. Lastly, a single lobe pertains to an orbital like the s orbital, which is singular and lacks the complexity of d orbitals. Therefore, the identification of the dx2-y2 orbital as having four lobes oriented along the x and y axes captures its unique geometric and energetic properties accurately.