Periodic Trends Flashcards
What happens to coulombic attraction as you go across a period?
It increases because there more protons
What happens to coulombic attraction as you go down a group?
It decreases because elections are further from the nucleus
What happens to the atomic radius as you go across a period?
The atomic radius decreases because the effectiveness of the nucleus decreases
Define atomic radius.
The distance between an atoms nucleus and it’s outermost electron
What happens to the atomic radius as you go down a group?
The atomic radius increases because the number of energy levels (n) increases, so there is a greater distance between the nucleus and the outermost orbital.
Why does ionization take energy?
Coulombic attraction makes it difficult to pull something out of the nucleus, so it requires energy
What happens to ionization energy down a group?
It decreases because the outermost electron is farther from the nucleus, meaning it is held less tightly and requires less energy to remove
What happens to ionization energy across a period?
Ionization energy increases because of increasing nuclear charge, which results in the outermost electron being more strongly bound to the nucleus
Relationship between metals and ionization energy
Hold atoms loosely so they have a low ionization energy
Coulombic attraction and electronegativity in groups
Both decrease
Coulombic attraction and electronegativity in periods
Both increase
Shielding Effect
the decrease in the nucleus’s force of attraction on valence electrons due to the existence of electrons in the inner shells.
Exceptions to the rules?
Sulfur and group 17
