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Flashcards in Periodic Trends Deck (11):
1

Cation

a positively charged ion
ex: H+

2

Anion

a negatively charged ion
ex: H-

3

Atomic Radii

the distance from the nucleus to the outermost electrons of an atom

4

Atomic Radii DECREASE across a PERIOD because . . .

there are more protons being added to the nucleus, which creates greater attraction to the electrons in each energy level, ultimately pulling the electrons closer to the nucleus making the atom smaller.

5

Atomic Radii INCREASE across a GROUP because . . .

the outer shells of each atom increase and an atom with more outer shells means electrons are held less tightly (shielding) --> further away from the nucleus

6

Electronegativity

measures how strongly an atom desires an electron

7

Electronegativity INCREASES across a PERIOD because

as the number of electrons increase, the more electrons are wanted in order to reach stability (8 electrons)

8

Electronegativity DECREASES down a GROUP because

there are more electrons being added (causing shielding) which causes the attraction between the nucleus and the electrons to decrease--> this makes it easy for the atom to give away an electron

9

Ionization Energy

energy required to remove an electron from an atom

10

Ionization Energy INCREASES across a PERIOD because

as you move across a period, atomic radius decreases --> outer electrons are therefore closer to the nucleus and are more strongly attracted to the center: DIFFICULT TO REMOVE OUTERMOST ELECTRON

11

Ionization Energy DECREASES down a GROUP because

the electrons are further away from the nucleus (shielding) and are either to remove