ch. 8- Atoms

Question 1

Elements

Answer 1

Matter that is composed of one type of atom

Question 2

Scientific shorthand

Answer 2

A letter or pair of letters called a chemical symbol

Question 3

Compounds

Answer 3

Form when two or more elements combine chemically

Question 4

Molecule

Answer 4

Smallest unit of any compound

Question 5

Atom

Answer 5

Smallest piece of matter that still has the properties of the element

Question 6

Nucleus

Answer 6

Located in the center of the atom

-made of protons and neutrons

Question 7

Protons

Answer 7

+1 charge

Question 8

Neutrons

Answer 8

Neutral charge/no charge

Question 9

Electrons

Answer 9

-1 charge

Question 10

Electron cloud

Answer 10

Model showing electrons traveling in specific energy levels around a nucleus

Question 11

Valence electrons

Answer 11

Electrons in outer shell

• highest energy
• involved in bonding

Question 12

Quarks

Answer 12

Smaller particles that make up protons/ neutrons

-only 6 known to exist

Question 13

Atomic mass

Answer 13

Protons + neutrons

-also called mass #

Question 14

Atomic #

Answer 14

# of protons in an atom 
- every elements has a different atomic #

Question 15

Isotopes

Answer 15

Atoms of the same element that have different #’s of neutrons

Question 16

Average Atomic Mass

Answer 16

Average mass of all isotopes of that element

Question 17

First periodic table:

Answer 17

• made by Dmitri Mendeleev i the late 1800’s

- based on atomic mass

Question 18

Periodic table used today

Answer 18

• made by Henry G. J. Mosley in 1913

- arranged by atomic #

Question 19

Groups

Answer 19

• vertical columns of elements with similar properties
• # 1-18
• elements in same group have same # of VE

Question 20

Periods

Answer 20

• horizontal rows of elements that contain increasing #’s or protons/ electrons
• numbered 1-7
• each row ends when an outer energy level is filled

Question 21

Metals location

Answer 21

-located to the left of the stairstep

Question 22

Metals properties

Answer 22

• react by losing VE
• good conductors of heat/ electricity
• solid at room temp. except mercury (Hg)

Question 23

Reactivity depends on what?

Answer 23

• how easily its atoms loses VE

- reactivity decreases from left to right

Question 24

What are the 3 metal types?

Answer 24

Alkali metals, alkaline earth metals, and transition metals

Question 25

Alkali metals

Answer 25

- group 1 elements - most reactive - don’t occur alone naturally

Question 26

Alkaline earth metals

Answer 26

- group 2 elements - shiny, ductile, malleable - combine readily with other elements - still very reactive

Question 27

Transition metals

Answer 27

- group 3-12 elements | - most familiar metals because they occur naturally uncombined

Question 28

Inner transition metals

Answer 28

- lanthanides series with atomic #’s 57-71 | - actinide series with atomic #’s 89-103

Question 29

Nonmetals

Answer 29

- become stable when they gain or share enough electrons to have 8 VE - usually combine with metals by gaining electrons - can combine with other nonmetals and metalloids by sharing electrons

Question 30

Halogens

Answer 30

- group 17 elements - contain 7 VE - react easily with other elements

Question 31

Noble gases

Answer 31

- group 18 elements - exist as isolated atoms - are stable bc outer energy level is filled

Question 32

Metalloids location

Answer 32

-make up stairstep

Question 33

Metalloids properties

Answer 33

- have metallic and non-metallic properties | - a part of the mixed groups

Question 34

Hydrogen

Answer 34

-considered a nonmetal

Question 35

Mixed groups

Answer 35

Contain metals, nonmetals, and metalloids | -group 13-17