Chapter 7: Periodic Proerties Of The Elements

Question 1

Effective nuclear charge trend

Answer 1

Increase left to right, Top to bottom

B/c more protons = greater effective nuclear charge (within a period) -> more pull on electrons
Shorter atomic radius (valence shell close to nucleus, less shielding) = greater effective nuclear charge -> more pull on electrons

Question 2

Atomic radius trend

Answer 2

Increasing right to left, top to bottom

B/c fewer protons -> less effective nuclear charge -> less pull on valence electrons
Increase in the period -> farther valence electrons

Question 3

Zeff = Z - S

Answer 3

Effective nuclear charge is smaller than nuclear charge b/c it takes into account electron shielding

S is screening costant, usually charge of the core electrons

equation only a rought estimate b/c eletrons might