a. He - Highest occupied energy level: 1s orbital
b. Be - Highest occupied energy level: 2s orbital
c. Al - Highest occupied energy level: 3p orbital
d. Ca - Highest occupied energy level: 4s orbital
e. Sn - Highest occupied energy level: 5p orbital
To determine the highest occupied energy level in an element, we need to look at its electron configuration. The electron configuration tells us how electrons are distributed in different energy levels or orbitals.
a. He (Helium) has an electron configuration of 1s², indicating that its highest occupied energy level is the 1s orbital.
b. Be (Beryllium) has an electron configuration of 1s² 2s², indicating that its highest occupied energy level is the 2s orbital.
c. Al (Aluminum) has an electron configuration of 1s² 2s² 2p⁶ 3s² 3p¹, indicating that its highest occupied energy level is the 3p orbital.
d. Ca (Calcium) has an electron configuration of 1s² 2s² 2p⁶ 3s² 3p⁶ 4s², indicating that its highest occupied energy level is the 4s orbital.
e. Sn (Tin) has an electron configuration of 1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d¹⁰ 4p⁶ 5s² 4d¹⁰ 5p², indicating that its highest occupied energy level is the 5p orbital.