Periodic Table Trends

Question 1

Atomic #

= #P & #N in a neutral atom

Answer 1

Def: #P

Trend: Fam.↑, Per.↑

Exp: for every new element you +1 more P so it ↑ as you move down a fam. & across a per.

Question 2

Atomic Mass

= P+N

Answer 2

Trend: Fam.↑, Per.↑

Exp: for every new element you +P& N so mass will ↑

Question 3

*Effective Nuclear Charge

Answer 3

Def: attractiveness of the nucleus, + force felt by e- (comes from P)

Trend: Fam.↓, Per.↑

FExp: new energy lvls added block the attractive force of nucleus so less attractive as you move ↓

PExp: no new energy lvls added so as new P are added the attractive force ↑, nucleus gets more attractive

Li vs F…Lady GaGa vs Channing Tatum…unattractive vs attractive

Question 4

Valence Electrons

Every atom dreams of having 8ve (*or filling their outer shell) *2ve: He,H,Li,Be,B

Answer 4

Def: e- in outermost energy lvl

Trend: Fam.same, Per.↑

FExp: new energy lvls added so same e- config. so same # of ve

PExp: no new energy lvls added so every new e- is a ve

Question 5

Charge

Atoms can obtain 8 (or 2) e- by either losing or gaining e-

Answer 5

Def: ion=charged particle

Trend: Fam.same, Per.+–>-

FExp: new energy lvls added so same e- config. so same # of ve leads to same charge

PExp: no new energy lvls added so ve ↑ meaning atoms will gain e- & have - charges as you move right

Question 6

Atomic Radius

1st energy level holds 2 e- & all others will hold 8* e-

Answer 6

Def: 1/2 the distance between the nuclei of 2 bonded atoms

Trend: Fam.↑, Per.↓

FExp: more e- added new energy lvls needed so radius bigger

PExp: no new energy lvls added so nucleus becomes more attractive & pulls e- in

Question 7

Electronegativity (en)

The closer an atom is 8ve the more it wants an e-

Halogens=↑en Noble Gases=↓en Alkali Metals=↓en

Answer 7

Def: the ability of an atom to attract e- AKA how badly an atom wants an e-

Trend: Fam.↓, Per.↑

FExp: new energy lvls added which block or shield the attractive force of nucleus nucleus is less attractive

PExp: no new energy lvls added so add more ve so atoms will want to gain e-

Question 8

Ionization Energy (IE)

Noble Gases=↑est IE b/c they have 8ve & are stable

Alkali Metals=↓est IE b/c they have 1ve & want to get rid of it is the family w/ the lowest

Answer 8

Def: amt. of energy needed to remove a ve EASY= ↓IE HARD=↑IE

Trend: Fam.↓ (KIDNAP), Per.↑

FExp: new energy lvls added so **atomic radius ↑ **& nucleus is less attractive b/c of shielding so e- is easier to remove

PExp: no new energy lvls added so nucleus is more attractive & closer to having 8ve so very hard to remove e-

Question 9

PERIOD trends →

Answer 9

• NO new energy lvls added
• nucleus is MORE attractive
• closer to having 8ve

Question 10

FAMILY trends ↓

Answer 10

• NEW energy lvls added
• nucleus is LESS attractive
• “block or shielding”