chem unit 5

Question 1

wavelength

Answer 1

The shortest distance between equivalent points on continuous waves.
usually expressed in meters,centimeters, or nanometer

Question 2

Frequency

Answer 2

the number of waves that pass a given point per second

Question 3

speed

Answer 3

the rate of distance per unit time.
- all electromagnetic radiation travels at the same speed (3.00 x108)

Question 4

amplitude

Answer 4

the height of a wave from the origin to the crest or from the origin to the trough

Question 5

biggest wavelenght to smallest

Answer 5

radio waves, microwaves, infrared, visible light, ultra-violet, X-rays, gamma rays

Question 6

which has the highest frequency

Answer 6

gamma rays

Question 7

equation 1

Answer 7

speed of light = wavelength multiply by velocity

Question 8

plank’s constant

Answer 8

6.626 x10-34 J.s

Question 9

Incandescence

Answer 9

making an object so hot it emits light
- different wavelength of light emitted at different temp
- light only be emitted with E are multiple of Hv

Question 10

Photoelectric effect

Answer 10

Electrons are ejected from a metal surface when light of a certain frequency shines on it.

Question 11

Photons

Answer 11

a particle of electromagnetic radiation that carries a quantum of energy

Question 12

atomic emission spectra

Answer 12

is the set of frequencies of that electromagnetic waves emitted by atoms of that element
- only certain colors are observed, which mean only certain frequencies are emitted
- elements absorb at the same frequencies they emit

Question 13

Niels Bohr Fix

Answer 13

• electrons only in allowed orbits
  -orbits prevent electrons from spiraling into the nucleus
  -orbits can be calculated mathematically
  -labeled energy levels (orbits) with quantium number (n)

Question 14

ground state

Answer 14

the lowest energy level or N=1

Question 15

what does the Bohr model explain

Answer 15

• explains the location of electrons
  -explained how elements behave chemically
  -explained the atomic spectrum of hydrogen or any 1e- species

Question 16

problem with Bohr model

Answer 16

-only explains the emission spectrum for hydrogen
- does not accurately describe the location of the electron
-conflict with Heisenberg uncertainty principle

Question 17

Heisenberg uncertainty principle

Answer 17

from the photoelectric effect, photons can eject an electron
-trying to see an electron disturbs it
- fundamentally impossible to know both position and velocity of the electrons

Question 18

energy levels

Answer 18

electrons have certain energy levels, N where N=1,2,3 etc
- for each energy level (n) there are n2 total orbitals

Question 19

Quantum mechanical model of the atom

Answer 19

• Erwin Shrodinger developed an equation to treat the electron as a wave
• works for hydrogen (simplifies to the bohr equation) and works for all other atoms
  -the model treating electrons as waves is the Quantum Mechanical Model of the atom

Question 20

electron density

Answer 20

can’t say exactly where the electron is, so use Electron density
Definition- probability that the e- is at a point in space

Question 21

high electron density

Answer 21

likely the electron is there

Question 22

low density

Answer 22

unlikely the electron is there

Question 23

how many orbitals does sublevel S have?

Answer 23

1

Question 24

how many orbitals does sublevel p have

Answer 24

3

Question 25

how many orbitals does sublevel d have

Answer 25

5

Question 26

how many orbitals does sublevel f have

Answer 26

7

Question 27

how many electrons are n each orbital

Answer 27

2

Question 28

s shaped orbital

Answer 28

sphere shape, centered on the nucleus

Question 29

p shaped orbital

Answer 29

dumb- bell shaped with 3 possible orientation on X-,y- or z axes

Question 30

d shaped orbital

Answer 30

clover shaped with 5 orientation (and one) dumb-bell with ring shape n the z axis
- 5 totald orbitals

Question 31

f shaped orbitals

Answer 31

complex shaped
- and f sublevel has 7 f-orbitals

Question 32

the higher the sublevel (n)

Answer 32

the lager/bigger the orbital

Question 33

Aufbau principle

Answer 33

an electron will occupy the lowest E orbital with space for it

Question 34

Pauli exclusion principle

Answer 34

if two electrons occupy the same orbital, they must have opposite spins

Question 35

hund’s rules

Answer 35

in ground state: within a sublevel, electrons won’t share an orbital unless they have to. Unpaired electrons will all have the same spin.