Unit 2

Question 1

Plank’s quantum theory

Answer 1

• heated objects emit light
• “black body problem” or “UV catastrophe”
• all electromagnetic energy is quantized

Question 2

photoelectric effect

Answer 2

• identities photons of light
• used by Einstein

Question 3

neils bohr

Answer 3

e- are found in specific orbits around the nucleus

Question 4

balmer

Answer 4

studied the e- transitions in H (refraction emission spectrum of H)

Question 5

heisenberg

Answer 5

there is a limit to what we know about a quantum system

Question 6

broglie

Answer 6

matter & radiation have properties of waves & particles

Question 7

schrödinger

Answer 7

developed an equation to describe the wave function of a system

Question 8

pauli exclusion principle

Answer 8

each e- has its own “address” in an atom

Question 9

aufbaw principle

Answer 9

e- are added from lowest–>highest E

Question 10

hund’s rule

Answer 10

every orbital is singly filled before it can be doubly filled

Question 11

mendeleev & meyer

Answer 11

electron config. & periodic table arranged by atomic mass & chemical reactivity

Question 12

moseley

Answer 12

relationship between x-ray diffraction & # P

Question 13

isoelectronic

Answer 13

same # e-
i.e. O^(2-) : [Ne]

Question 14

in e- config., transition metals

Answer 14

lose their S electrons first

Question 15

metallic character

Answer 15

increases: left/down

Question 16

effective nuclear charge (Zeff)

Answer 16

increases: up/right

Question 17

atomic radii

Answer 17

increases: left/down

Question 18

ionic radii

Answer 18

• cations have smaller radii than neutral
• anions have larger radii than neutral

Question 19

ionization energy

Answer 19

• increases: up/right
• E required to remove outermost e- from an isolated neutral atom in the gaseous state

Question 20

1st ionization energy

Answer 20

X(g) + energy –> X^(+)(g) + e-

Question 21

2nd ionization energy

Answer 21

X^(+)(g) + e- –> X^(2+)(g) + e-

Question 22

400 nm

Answer 22

gamma (high E; low wavelength)

Question 23

700 nm

Answer 23

radio (low E; high wavelength)

Question 24

n

Answer 24

• principle quantum #
• # shells

Question 25

l

Answer 25

- angular momentum quantum # - shape of orbital - l = n-1

Question 26

m(sub l)

Answer 26

- magnetic quantum # - orientation of orbital - -l...+l

Question 27

m(sub s)

Answer 27

- electron spin quantum # - -1/2 OR +1/2