periodic table Flashcards
atomic radius across a period
The atomic radius decreases across a period. The effective nuclear charge or # of protons increases the attraction of the nucleus and therefore pulls the electron cloud closer to the nucleus
atomic radius down a group
The atomic radius increases down a group. The increased number of energy levels (n) increases the distance over which the nucleus must pull. This reduces attraction for electrons. Full inner energy levels provide some shielding between the nucleus and valence electrons.
ionization energy in a period
Ionization energy increases across a period due to the higher number of of protons creating more attraction causing the nucleus to hold the electrons tightly
ionization energy in a group
Ionization energy decreases as you go down a group due to the higher number of p.e.l increases, creating more distance between the nucleus and electrons, making it easier to remove electrons.
electronegativity across a period
Electronegativity increases across a period because there are more protons as you go across, increasing the attraction between nucleus and e-‘s.
electronegativity down a group
Electronegativity decreases as you go down a group due to the higher number of p.e.l.s which creates more distance between the nucleus and electrons.
Do positive ions have a larger or smaller ionic radius than its original atom?
Positive ions have a smaller ionic radius because they are losing valence electrons, making it smaller.
Do negative ions have a larger or smaller ionic radius than its original atom?
Negative ions have a larger ionic radius because they are gaining valence electrons, making them bigger.
Are metals more reactive as you move up or down a column.
Metals are more reactive going down a column. Metals react by losing electrons. An increased # of energy levels comes with increased distance from the nuclear attraction, leaving looser held electrons.
Are nonmetals more reactive as you move up or down a column?
Nonmetals are more reactive as you move up because they tend to gain electrons, so there would be a stronger nuclear charge due to the lower number of p.e.l.
What is ionization energy?
The energy required to remove the most loosely bound electron from an atom in the gas state
What is an atomic radius?
Half the distance between nuclei of identical atoms bonded together
What is electronegativity?
A measure of the attraction of a nucleus for a bonded electron
What is electron affinity?
The amount of energy released when an electron is added to a neutral atom to from an anion
What is a cation?
A positively charged ion
