To calculate the effective nuclear charge of a 3d electron of cobalt, you will need to understand two concepts: the atomic number and the shielding effect.
The atomic number represents the number of protons in the nucleus of an atom. For cobalt (Co), the atomic number is 27.
The shielding effect refers to the idea that outer electrons are shielded or screened from the full attractive force of the nucleus by the inner electrons. Electrons closer to the nucleus exert a repulsive force on the outer electrons, effectively reducing the attractive force experienced by those outer electrons.
Here are the steps to calculate the effective nuclear charge of a 3d electron for cobalt:
Step 1: Determine the number of inner electrons. To do this, count the number of electrons present in lower energy levels than the 3d orbital. For cobalt, the electron configuration is 1sĀ² 2sĀ² 2pā¶ 3sĀ² 3pā¶ 4sĀ² 3dā·. In this case, the inner electrons consist of the 1sĀ² 2sĀ² 2pā¶ 3sĀ² 3pā¶ core electrons. Therefore, there are a total of 21 inner electrons.
Step 2: Calculate the shielding effect. The shielding effect is given by the formula: Shielding effect = Number of inner electrons - 1. In this case, the shielding effect is 21 - 1 = 20.
Step 3: Calculate the effective nuclear charge. The effective nuclear charge is given by the formula: Effective nuclear charge = Atomic number - Shielding effect. In this case, the effective nuclear charge is 27 - 20 = 7.
Therefore, the effective nuclear charge of a 3d electron of cobalt is 7.