Periodic Trends Flashcards
Which trend across the periodic table is the opposite of all the other trends?
Atomic radius
How to compare ionization energies of elements?
They increase from left to right and from bottom to top on the periodic table
How to compare Zeff of elements?
They increase from left to right and from bottom to top on the periodic table
–> The smaller and the lowest n: the higher the Zeff
How to compare electronegativity?
They increase from left to right and from bottom to top on the periodic table
How to compare electron affinities?
As atomic radius increases, electron affinity decreases, and atoms that need less electrons to complete their shells will have higher electron affinity.
How to compare ionic radii of elements?
- Compare number of protons = largest nuclei
2. Compare number of electrons = largest ionic nuclei
What is the ionization energy of an element?
The energy required to remove 1 electron from a gaseous species
How to assess periodic trends?
Look at which atom is the closest from the corner!!
How to compare ionization energies when the atoms are equidistant from the upper right corner?
Look at which one has less electrons –> this one has a lower Zeff, so it has a lower ionization energy!
What does Zeff represent?
The strength with which the protons in the nucleus can pull on electrons, so the highest effective nuclear charge will be the atoms with the most protons relative to electrons.
Why does atomic radius decrease from left to right on the periodic table?
Because of the effects of shielding: there are more electrons on the outter shell to counteract the shielding of the electrons in the inner shell, which means the electrons can get closer to the nucleus
Why does atomic radius increase from top to bottom on the periodic table?
Because you are adding electrons to the outter shell (think of shielding)
