The values of the shielding constant (S) and the effective nuclear charge (Z*) for the 3d electrons in Copper (Cu) are respectively?
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To find the values of the shielding constant (S) and the effective nuclear charge (Z*) for the 3d electrons in Copper (Cu), we need to examine the electron configuration of copper.
The electron configuration of copper can be represented as: [Ar] 3d^10 4s^1.
In this configuration, the 3d electrons are shielded by the electrons in the inner shells, which are represented by the noble gas configuration [Ar]. The noble gas configuration refers to the electron configuration of the previous noble gas, in this case, Argon (Ar), which has the electron configuration 1s^2 2s^2 2p^6 3s^2 3p^6.
The shielding constant (S) represents the extent to which the outer electrons are shielded from the full nuclear charge. In copper, the first 3d electron experiences a certain level of shielding from the previous 2s^2 and 2p^6 electrons in the [Ar] configuration.
On the other hand, the effective nuclear charge (Z*) refers to the net positive charge that the outer electrons in an atom experience after taking into account the shielding effect. It can be calculated by subtracting the shielding constant (S) from the actual nuclear charge (Z).
The actual nuclear charge for copper (Cu) is 29 (since copper has an atomic number of 29).
To determine the value of the shielding constant (S) and the effective nuclear charge (Z*) for the 3d electrons in copper, we can compare the electron configuration of copper with the noble gas configuration of argon.
Based on the electron configuration, we can see that the 3d electrons in copper experience a full shielding effect from the previous noble gas configuration [Ar] since it is completely filled with electrons.
Therefore, the shielding constant (S) for the 3d electrons in copper is equal to the total number of electrons in the previous noble gas configuration, which is 18 (2 from 2s^2 and 16 from 2p^6).
To find the effective nuclear charge (Z*), subtract the shielding constant (S) from the actual nuclear charge (Z). In this case, Z* = Z - S = 29 - 18 = 11.
Hence, the values of the shielding constant (S) and the effective nuclear charge (Z*) for the 3d electrons in copper (Cu) are 18 and 11, respectively.