Periodic trends Flashcards
Name the four different trends in the periodic table
Atomic Radius, Ionization energy, electron affinity and electronegativity
What is Zeff?
Zeff is effective nuclear charge, the equation is Zeff= Z-S
What do the Z and S stand for in zeff
Z= nuclear charge (number of protons in the nucleus) S= how many electrons are between the nucleus and the valence electrons (Zeff stays the same down a group)
What is Atomic Radius?
The size of an atom in pictometers
what happens to atomic radius down a group
Increases (as the electrons increase the number of shells increase resulting in a larger radius)
what happens to atomic radius across a period?
the atomic radius decreases as you move across a period (left to right)
What is ionization energy (IE)
the amount of energy required to remove an electron from an atom or ion
What happens to ionization energy as you move down a group
Down a group the ionization energy decreases
What happens to ionization energy across a period?
As you move across a period the ionization energy increases
what is electron affinity
the energy change when an electron is added to an atom
What happens to electron affinity when you go down a group?
It decreases
What happens to electron affinity across a period?
Across a period (left to right) the electron affinity increases (because of “increased nuclear attraction”)
what is electronegativity?
The ability of an atom in a bond to attract shared electrons
what happens to electronegativity as you move down a group?
As you move down a group it decreases
What happens to electronegativity across a period
electronegativity increases across a period
