ch 7 8

Question 1

metallic character and its trends

Answer 1

-good conductors
-malleable
-ductile
-shiny
-readily loses e- to become stable

Moving across period: D
Moving down a group: I

Question 2

Trends of electron affinity

Answer 2

Moving across period: more N
Moving down a group: no trends EXCEPT group 1.. more P as moving down group

Question 3

Coulomb’s law

Answer 3

the force of attraction is inversely proportionate to the distance between charged particles

Question 4

red vs green vs blue
visible light vs x rays vs microwaves
lowest, mid, highest

a) wavelength
b) frequency
c) energy per photon

Answer 4

a) blue, green, red
b) red, green, blue
c) red, green, blue

a) x rays, visible, microwaves
b) microwaves, visible, x rays
c) microwaves, visible, x rays

Question 5

what does the energy of the photon represent

Answer 5

the difference in energy between an atom’s initial and final state (excited vs ground state)
E= hv

Question 6

shapes of these sublevels
a) s
b) p
c) d
why is the shape important?

Answer 6

s= spherical
p= dumbbell
d= double dumbbell

shape is important because bonds exist at overlapping sublevels

the shape of the overlapping orbital determines the shape of the molecule

Question 7

Pauli exclusion principle

Answer 7

orbitals can hold no more than 2 electrons each

Question 8

Hund’s rule

Answer 8

electrons occupy orbitals of identical energy with parallel spins rather than in pairs, they start to pair when orbitals are half full

Question 9

finding d block and f block

Answer 9

d: n-1
f: n-2

Question 10

Trends of ionization nrg and EN

Answer 10

EN: F is the most EN element, decreases as moving further away

IE: increases going across a period, decreases going down a group

Question 11

how does level of penetration and shielding determine PE

Answer 11

less shielding= greater nrg
more penetration= greater nrg

Question 12

lattice nrg and its relationship to AR

Answer 12

E= (q1q2)/r
lattice nrg= energy change occurring when gaseous ions react to form a solid ionic compound

as AR decreases, LE gets larger but decreases BECAUSE q1q2 will always be a negative number

larger amount of nrg= very stable

Question 13

bond strength and length order

Answer 13

strength: single < double < triple
length: single > double > triple BECAUSE a stronger bond will pull e to nucleus more making AR smaller

Question 14

EN difference chart

Answer 14

Small (0-0.4) nonpolar covalent
Intermediate (0.4-2.0) polar covalent
Large (2.0) ionic

Question 15

percent ionic character

Answer 15

degree to which an electron is actually transferred
greater than 50% is considered ionic

Question 16

finding number of pairs in molecule

Answer 16

(total number valance e)/2

Question 17

resonance and characteristics

Answer 17

two or more Lewis structures with the same skeletal formula (atoms in the same location) but different electron arrangements

*delocalized electrons have lower energy
*formal charge is used to determine most probable resonance structure (determines stability)

Question 18

calculating formal charge

Answer 18

(valance e) - (e atom “owns)
the sum of all formal charges must be zero in a neutral molecule

small or 0 former charges are better than large ones

Question 19

free radical

Answer 19

odd number of total valance e

Question 20

expanded octet

Answer 20

element in p 3-7
more than 8 valance e

Question 21

endo vs exo rxns have weak vs strong bonds formed vs broken?

Answer 21

endo: strong broken, weak formed
exo: weak broken, strong formed