Question

in which orbitals would the valence electrons for selenium (se) be placed?
s orbital and f orbital
s orbital only
s orbital and p orbital
d orbital only

Explanation:

Selenium has atomic number 34. Its electron - configuration is [Ar] 3d¹⁰4s²4p⁴. The valence electrons are in the 4s and 4p orbitals.

Answer:

C. s orbital and p orbital