How many unpaired electrons does Gadolinium have?

Gadolinium, which has the atomic number 64, belongs to the lanthanide series of the periodic table. Its electron configuration is [Xe] 4f^7 5s^2. In this configuration, the 4f subshell contains 7 electrons, which are arranged according to Hund's rule. This means that the electrons will occupy separate orbitals in the f subshell as much as possible before pairing up.

In Gadolinium's case, the 4f subshell comprises 7 electrons occupying the available orbitals, resulting in 7 unpaired electrons. This characteristic is significant as it relates to the magnetic properties of Gadolinium, making it particularly useful in various applications, including MRI contrast agents, due to its strong magnetic moment.

Understanding the electron configuration and the distribution of electrons within the orbitals is essential for determining the number of unpaired electrons in an element. The unique properties stemming from these unpaired electrons are what lead to the applications of Gadolinium in medical imaging and other technologies.