What is the effective nuclear charge (Z_eff) for a 3s electron in sodium (Z=11)?
Practice Questions
Q1
What is the effective nuclear charge (Z_eff) for a 3s electron in sodium (Z=11)?
1
3
8
11
Questions & Step-by-Step Solutions
What is the effective nuclear charge (Z_eff) for a 3s electron in sodium (Z=11)?
Step 1: Identify the atomic number (Z) of sodium. Sodium has an atomic number of 11.
Step 2: Understand that effective nuclear charge (Z_eff) is calculated using the formula Z_eff = Z - S.
Step 3: Determine the shielding constant (S) for the 3s electron in sodium. According to Slater's rules, the 1s and 2s electrons contribute to shielding.
Step 4: Count the number of electrons in the inner shells (1s and 2s) that shield the 3s electron. For sodium, there are 3 such electrons (2 from 1s and 1 from 2s).
Step 5: Assign the value of S as 3, since there are 3 inner electrons that shield the 3s electron.
Step 6: Substitute the values into the formula: Z_eff = 11 (Z) - 3 (S).
Step 7: Calculate Z_eff: 11 - 3 = 8.
Step 8: Conclude that the effective nuclear charge (Z_eff) for a 3s electron in sodium is 8.
