Question

what is the ground - state electron configuration expected for cesium?
xe 3d¹
xe 6s¹
xe 1s¹
xe 5p¹
question 6
what is the electron configuration of p⁺?
1s² 2s² 2p⁶ 3s 3p³
1s² 2s² 2p⁶ 3s² 3p³
1s² 2s² 2p⁶ 3s² 3p⁴
1s² 2s² 2p⁶ 3s² 3p²

Explanation:

Question 5

Cesium (Cs) has an atomic number of 55. Xenon (Xe) has an atomic number of 54. The next electron after Xe (which fills up to \(5p^6\)) goes to the \(6s\) orbital. The electron configuration of Cs is \([Xe]6s^1\) as the \(6s\) orbital is the next available orbital after the noble - gas core of Xe. The \(3d\) orbital is filled much earlier (in the transition metals of the 4th period), the \(1s\) orbital is the first orbital (for hydrogen - like species with very low atomic numbers), and the \(5p\) orbital is already filled in Xe.

The atomic number of phosphorus (P) is 15. The electron configuration of \(P\) is \(1s^{2}2s^{2}2p^{6}3s^{2}3p^{3}\). When \(P\) loses one electron to form \(P^{+}\), it loses an electron from the highest - energy orbital. The highest - energy orbital in \(P\) is the \(3p\) orbital. So, the electron configuration of \(P^{+}\) is \(1s^{2}2s^{2}2p^{6}3s^{2}3p^{2}\)

Answer:

\([Xe]6s^1\) (the second option)

Question 6