Chem trends

Question 1

Scientists:

Answer 1

Lavoisier: got lists
Newlands: organized by atomic mass
Mendeleev: gets credit, made predictions.
Moseley: arranged by atomic number

Question 2

Periodic Law

Answer 2

when elements are in increasing atomic #, they are w/ similar properties at regular intervals.

Question 3

Periodicity

Answer 3

patterns in groups (vertical) and periods (horizontal)

Question 4

atomic radius

Metallic

Answer 4

half the distance of nuclei.

increases to LEFT and BOTTOM

Question 5

• ionization energy: energy required to remove 1 electron from neutral atom. increases at
• electron affinity: e- is gained
• electronegativity: measure of ability to attract electrons

Answer 5

increases TOP and RIGHT

Question 6

ionic radius

Answer 6

distance from center to outer e- increases at BOTTOM and right

Question 7

Metallic bonds

Answer 7

attractions of cation to delocalized electrons, good conductors

Question 8

metals, ionic

Answer 8

shiny, malleable/ductile, high melting points.

Question 9

covalent

Answer 9

weak bond, low melting point

Question 10

nonpolar covalent

Answer 10

e- shared equally

Question 11

polar

Answer 11

e- shared unequally, diff in electronegativity

Question 12

Lewis structures

Answer 12

• H always outside

- C always center

Question 13

bond energy

Answer 13

energy required to break a bond. strongest= shortest and triple. 2,4,6

Question 14

exceptions to octet rule

Answer 14

• Boron likes to have 6

- s,p,br,i,xe have more than 8

Question 15

vsepr thoery

Answer 15

used to predict molecular geometry of covalent. repulsion of valence

Question 16

hybridization

Answer 16

mixing atomic orbitals. group 15&16
linear; sp
trignomial planar; sp2
tetrahedral; sp3

Question 17

metals

Answer 17

left, not hydrogen. valence 1 and 2. solid, shiny, good conductors, malleable and ductile. reactivity increases down left

Question 18

nonmetals

Answer 18

top right and hydroge. 4, 5, 6, 7,8. dull brittle poor conductors not malleable. reactivity increases up and right

Question 19

transitional metals

Answer 19

high melting points, covalent, good conductors, hard to bent/hammers

Question 20

alkali metals

Answer 20

group 1,soft, silvery, low boiling point. found naturally in nature. very reactive w/ water

Question 21

alkaline earth metal

Answer 21

soft silver,

Question 22

halogens

Answer 22

group 17, toxic, nonpolar covalent. most reactive in nonmetal.

Question 23

Lanthanide and Actinides

Answer 23

L: abundant, tarnish, dissolve. reacts w/ halogens
A:rare earth metals, man made, radioactive, toxic, nuclear energy

Question 24

Noble gases

Answer 24

group 18, non reactive. low boiling point. oderless and colorless. extremely rare

Question 25

Hydrogen/Helium

Answer 25

Helium:2nd abundant, raises pitch of voice, 2nd least reactive. low boiling point, lighter than air (balloon)
Hydrogen: most abundant, light, reactive. becomes Helium

Question 26

Boron family

Answer 26

group 13, metallic, silvery white nonmetal except for boron

Question 27

carbon family

Answer 27

group 14 carbon is a non-metal, silicon and germanium are metalloids, and tin and lead are poor metals.

Question 28

Nitrogen family

Answer 28

group 15. melting point increse down the group

Question 29

oxygen family, chalogen

Answer 29

ch. 16 found in pure form in nature