Effective Nuclear Charge Video Lessons

Concept

# Problem: Classify each statement about effective nuclear charge, Zeff, as true or false.1. A 1s electron in a B atom has a smaller Zeff than a 1s electron in a Be atom.2. Effective nuclear charge does not depend on the number of electrons present in an atom.3. Across a period, as Zeff increases, atomic size increases.4. Effective nuclear charge increases from left to right across a period on the periodic table.5. In a Be atom, 1s electron has a greater Zeff than a 2s electron.6. Electrons in an s orbital are more effective than those in other orbitals at shielding other elctrons from nuclear charge.

###### FREE Expert Solution

Analyze each given statement:

1. A 1s electron in a B atom has a smaller Zeff than a 1s electron in a Be atom.

Zeff = Z – S

the 1s electron will have the same shielding constant (S) to another 1s electron

Z of B =  5
Z of Be = 4
Zeff of B > Zeff of Be

Statement → FALSE

2. Effective nuclear charge does not depend on the number of electrons present in an atom.

Zeff = Z – S

the total shielding (S) an electron feels depends on its location and the number of electrons before it

Statement → FALSE

3. Across a period, as Zeff increases, atomic size increases.

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###### Problem Details

Classify each statement about effective nuclear charge, Zeff, as true or false.

1. A 1s electron in a B atom has a smaller Zeff than a 1s electron in a Be atom.

2. Effective nuclear charge does not depend on the number of electrons present in an atom.

3. Across a period, as Zeff increases, atomic size increases.

4. Effective nuclear charge increases from left to right across a period on the periodic table.

5. In a Be atom, 1s electron has a greater Zeff than a 2s electron.

6. Electrons in an s orbital are more effective than those in other orbitals at shielding other elctrons from nuclear charge.