Of the atoms listed below, which one will have at least one electron in its d orbital?

D. Cr

Explanation:

In order to determine which atom has at least one electron in its d orbital, we have to write their theoretical electron configurations.

Cr has 4 electrons in d orbitals. Cr belongs to the d-block in the periodic table.

A waning moon is the moon that decreases in size and its illumination . Moon starts waning a day after the full moon. Its size keeps decreasing and ultimately it is not visible on the new moon day.

A waning moon looks like it is getting smaller. The left side of the moon is smooth and round while the right side of a waning moon appears blurred.

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