A possible set of quantum numbers for the last electron added to complete an atom of gallium (Ga)in its ground state is

Question

Quizplus · Accepted Answer

The last electron added to complete an atom of Ga is the 31st electron. To determine the possible set of quantum numbers for this electron, we can use the Aufbau principle and fill the orbitals in increasing order of energy.

1s2, 2s2, 2p6, 3s2, 3p6, 4s2, 3d10, 4p1

The last electron added is in the 4p orbital. Therefore, the values of n, l, and ml for this electron are 4, 1, and either -1, 0, or 1, respectively. The value of ms (the spin quantum number) is either +1/2 or -1/2.

Looking at the answer choices, only option C has the correct values for n, l, ml, and ms. The other options either have incorrect values or are missing information.

A Possible Set of Quantum Numbers for the Last Electron