Explanation of the Electronic Configuration of Ni, Pd, and Pt

Introduction
Ni (Nickel), Pd (Palladium), and Pt (Platinum) belong to the same group in the periodic table, which is group 10. The elements in this group are known as the transition metals. They possess similar chemical and physical properties, but their electronic configurations are different.

Electronic Configuration of Ni
Nickel has an atomic number of 28, which means it has 28 electrons. The electronic configuration of Ni is [Ar] 3d8 4s2. The [Ar] represents the electron configuration of Argon, which is the noble gas that comes before Ni in the periodic table. The 3d8 represents the eight electrons in the d orbital of the third energy level, while the 4s2 represents the two electrons in the s orbital of the fourth energy level.

Electronic Configuration of Pd
Palladium has an atomic number of 46, which means it has 46 electrons. The electronic configuration of Pd is [Kr] 4d10. The [Kr] represents the electron configuration of Krypton, which is the noble gas that comes before Pd in the periodic table. The 4d10 represents the ten electrons in the d orbital of the fourth energy level.

Electronic Configuration of Pt
Platinum has an atomic number of 78, which means it has 78 electrons. The electronic configuration of Pt is [Xe] 4f14 5d9 6s1. The [Xe] represents the electron configuration of Xenon, which is the noble gas that comes before Pt in the periodic table. The 4f14 represents the fourteen electrons in the f orbital of the fourth energy level, while the 5d9 represents the nine electrons in the d orbital of the fifth energy level, and the 6s1 represents the one electron in the s orbital of the sixth energy level.

Explanation of the Differences in Electronic Configuration
The differences in the electronic configurations of Ni, Pd, and Pt can be attributed to the Aufbau principle, which states that electrons fill the lowest energy levels first before moving to higher energy levels. The electronic configuration of Ni follows the Aufbau principle, with the 4s orbital filled before the 3d orbital. The electronic configuration of Pd is an exception to the Aufbau principle, with the 4d orbital filled before the 5s orbital. The electronic configuration of Pt is also an exception to the Aufbau principle, with the 5d orbital filled before the 6s orbital. These exceptions can be explained by the fact that the 4d and 5d orbitals have slightly lower energy than the 5s and 6s orbitals, respectively. Therefore, it is energetically favorable for the electrons to occupy the d orbitals before the s orbitals.

Conclusion
In conclusion, Ni, Pd, and Pt belong to the same group in the periodic table but have different electronic configurations. These differences can be explained by the Aufbau principle and the energetically favorable occupation of d orbitals before s orbitals in Pd and Pt.

Depends upon the atomic no. as atomic no. increases mass of the atom increases nd hence atomic radius increases so if they have more electrons in outermost orbit apart from complete octet then have tendency todonate electrons to acceptor atoms