MIDTERM STUDY (unit 3)

Question 1

Nucleus contains almost all of…

Answer 1

atom’s mass (p+ and n0)

Question 2

Electron cloud contains almost all of…

Answer 2

atom’s volume (e-)

Question 3

One amu = to what?

Answer 3

1/12 the mass of the carbon-12 atom

Question 4

Balance between what holds atom together?

Answer 4

between electrostatic repulsion of like charges and electrostatic attraction of opp charges

Question 5

Electron abt_________ the size of a proton

Answer 5

1/1800

Question 6

Hyphen notation:

Answer 6

mass # written w/ hyphen after element name

Question 7

Nuclear Symbol:

Answer 7

subscript = atomic #
superscript = mass #

Question 8

Mass of particular isotope is = to?

Answer 8

protons + neutrons

Question 9

of protons = ?

(Counting Subatomic Particles)
# of protons = ?

Answer 9

atomic #

Question 10

of neutrons =?

(Counting Subatomic Particles)
# of neutrons = ?

Answer 10

Mass # - atomic #

Question 11

of electrons = ?

(Counting Subatomic Particles) # 0f electrons = ?

Answer 11

atomic # ( in a neutral atom)

Question 12

Isotopes:

Answer 12

atoms of the same element (same # p+) w/ diff # of n0 = diff mass

Question 13

Some isotopes are…

Answer 13

stable and radioactive

Question 14

Ions:

Answer 14

lost/gained e-

Question 15

Cations:

Answer 15

(positive metals) formed when atoms lose e-

Question 16

Anions:

Answer 16

(negative non-metals) Formed when atoms gain e-

Question 17

Isotopes differ in # of n0 so differ in

Answer 17

MASS

Question 18

Atoms differ by # of

Answer 18

protons

Question 19

Ions differ by # of

Answer 19

electrons

Question 20

isotopes differ by # of

Answer 20

neutrons

Question 21

Average atomic mass:

Answer 21

weighted average of an element’s naturally occurring isotopes

Question 22

(order) History of Development of ATomic Model:

Answer 22

• greek/ Dalton Billiard ball model
• Thompson’s Plum pudding Model
• Rutherford’s Nuclear model
• Bohrs Planetary model
• Quantum Mechanical model

Question 23

Billiard ball model:

Answer 23

-Democtritus
-tiny solid, indestructible particles

Question 24

Plum Pudding Model

Answer 24

-J.J thompson
- solid sphere w/ negativly charged e- embedded in ti

Question 25

Rutherford model

Answer 25

• Earnest Rutherford
• atom is tiny, positively charged
• dense center
• mostly empty space

Question 26

bohr’s Model (Planetary Model)

Answer 26

-Niels Bohr

Question 27

Quantum mechanical model of the atom

Answer 27

-Many scientists

Question 28

1ST advancement ( ball to plum) :

Answer 28

Thompson discovered (-) particles (electrons)

Question 29

2ND advancement (plum to Ruther) :

Answer 29

Rutherford discovered atomic radius

Question 30

3RD advancement (Ruther to Planetary) :

Answer 30

idea of fixed orbits (electrons traveling around)

Question 31

LAWS AND THEORIES IN ORDER:

Answer 31

-Law of conservation of Matter
- Law of Definite Proportions
- Law of Multiple proportions
- Daltons Atomic theory
- QUantum Theory

Question 32

The mole:

Answer 32

Unit of quantity -> 6.022 x 10 >23
atoms, formula units, molecules, grams, Liters ( LAFUMG)

Question 33

Avogadro’s #:

Answer 33

6.022x10 >23

Question 34

Liters to moles =

Answer 34

22.4L/mol