Calcium (Ca) has the atomic number 20, and its electron configuration is [Ar] 4s². The valence electrons for calcium are in the 4th energy level (n=4).
To find an element that has atoms with valence electrons in a higher energy level than those of calcium, you should look for elements in period 5 or higher, as they have their valence electrons in the 5th energy level (n=5) or higher.
An example of such an element is rubidium (Rb), which has the atomic number 37 and an electron configuration of [Kr] 5s¹. The valence electron of rubidium is in the 5th energy level (n=5), which is higher than the 4th energy level of calcium.
So, a suitable answer is rubidium (Rb).
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