Chemistry Chapter 7

Front 1

electromagnetic radiation

Back 1

energy propagated by means of electric and magnetic fields that alternately increase and decrese in intensity as they move through space.(ex. visible light, x-rays, microwaves, and radio waves)

Front 2

frequency(v)

Back 2

the number of cycles the wave undergoes per second and is expressed in units of 1/s or Hz.

Front 3

wavelength(lambda)

Back 3

the distance between any point on a wave and the corresponding point on the next crest (or trough) of the wave, that si, the distnace teh wave travels during one cycle. Expressed in meters.

Front 4

speed of wave

Back 4

the distance a wave travels per unit of time(m/s), the product of frequency times wavelength.

Front 5

speed of light (c)

Back 5

in avacuum all ypes of eleectroagnetic radiation travel at 2.99792458 X 10^8 m/s

Front 6

amplitude

Back 6

the height of the crest(or depth of the trough)of each wave.

Front 7

intensity

Back 7

brightness in the case of visible light.(dimmmer=lower amplitude, brighter=higher amplitude).

Front 8

electromagnetic spectrum

Back 8

all waves travel at the same speed througha vacuu but differ in frequency and therefore, wavelength.

Front 9

infrared region(IR)

Back 9

the region of the electromagnetic spectrum that is between the microwave and visible regions.

Front 10

monochromatic

Back 10

the light of a single wavelength

Front 11

polychromatic

Back 11

the light of many wavelengths. (ex. white light)

Front 12

ultraviolet (UV) radiation

Back 12

the region adjacent to visible light on the short-wavelength end.

Front 13

refraction

Back 13

a phenomenon in which a wave changes its speed and therefore its direction as it passes through a phase boundary.(light in water)

Front 14

angle of refraction

Back 14

depends on the materials on either side of teh boundary and hte wavelength of the light, the new angle aftera wave strikes the boundary between air and water at an angle greater than 90 degrees, the change in speed causes a change in direction, and the wave continues at a different angle.

Front 15

dispersion

Back 15

white light separates(disperses)into its component colors becasue each incoming wave is refracted at a slightly different angle. (ex. light through a prism)

Front 16

diffraction

Back 16

the phenomenon in which a wave striking the edge of an object bends around it. A wave passing through a slit as wide as its wavelength forms a circular wave.(ex. pebble thrown into water).

Front 17

interference

Back 17

if waves of light pass through two adjacednt slits, teh emerging circular waves interact with each other through this process.

Front 18

blackbody radiation

Back 18

light given off by an idealizeed object hat absorbs all the radiation incident on it, changes in intensity and wavelength of an emitted light as an object is heated are characteristic of this.

Front 19

blackbody

Back 19

a hollow cube with a small hole in one wall approximates this.

Front 20

quantum

Back 20

a packet of energy equal to hv. The smallest quantity of energy that can be emitted or absorbed.

Front 21

quantum number

Back 21

a number that specifie s a property of a orbital or an electron.

Front 22

Planck's constant

Back 22

h=6.62606876 X 10^-34 Js

Front 23

quantized

Back 23

an atom itself can only emit certain quantities of energy, and the atom can have only certain quantities of energy, it exists only in certain fixed quantities rather than being continuous.

Front 24

quantum

Back 24

an "energy packet"

Front 25

photoelectric effect

Back 25

the flow of current when monochromatic light of sufficient frequency shines on a metal plate.

Front 26

photons

Back 26

"bundles" of electromagnetic energy, a quantum of electromagentic radiation.

Front 27

line spectrum

Back 27

a series of fine lines of individual colors separated by colorless (black) spaces, discrete(appears for light of different gases, like hydrogen, not continuous like sunlight).

Front 28

Rydberg equation

Back 28

predict the position adn wavelength of any line in a given series. -1/λ=R(1/(n1^2 )-1/(n2^2 ),)λ is the wavelength of a spectral line, n1 and n2 are positive integers with n2>n1 and R is the Rydberg constant.

Front 29

Rydberg Constant

Back 29

1.096776x10^7 1/m,

Front 30

stationary states

Back 30

in the Bohr model, one of teh allowable energy levels of the atom in which it does not release or absorb energy.

Front 31

ground state

Back 31

when the atom is in its lowest(first) energy level

Front 32

excited state

Back 32

when an electron is in the second or any higher orbit, it is said to be...

Front 33

zero point of the atom's energy

Back 33

when the electron is completely removed from the nucleus, when E=0, n=∞, E<0 for any smaller n

Front 34

ionization energy

Back 34

the amount of energy required to remove one electron from an atom to form a cation.

Front 35

de Broglie wavelength

Back 35

matter behaves as though it moves in a wave λ=h/mu

Front 36

wave-particle duality

Back 36

The principle stating that both matter and energy have wavelike adn particle-like properties.

Front 37

Heisenberg uncertainty principle

Back 37

it is impossible to know the exact positoiin and momentum(mass times speed) of a particle simultaneously. ΔxmΔu≥h/4π

Front 38

quantum mechanics

Back 38

a field that examines the wave nature of objects on the atomic scale.

Front 39

wave function

Back 39

a mathematical description o fthe electron's matter-wave in terms of position in three dimensions.

Front 40

atomic orbital

Back 40

each solution t othe Schrodinger equation(each energy state of the atoms is associated with a given wave function.

Front 41

probability density

Back 41

a measure of the probability that the electron can be found within a particular tiny volume o fte atom

Front 42

electron density diagram

Back 42

for a given energy level we can depict the probability density.

Front 43

radial probability distribution plot

Back 43

the graphic depiction of the total prbability distribution of an electron in the region near the nucleus.

Front 44

probability contour

Back 44

show the volume within which the electron o fhte hydrogen atom spends 90% of its time.

Front 45

principle quantum number(n)

Back 45

a positive integer (1,2,3, and so forth) indicates the relative size of the orbital and therefore the relative distance from the nucleus fo the peak in the radial probability distribution plot, specifies the energy level of the H atom.

Front 46

angular momentum quantum number(l)

Back 46

an integer from 0 to n-1, related to the shape of the orbital

Front 47

magnetic quantum number(ml)

Back 47

an integer from -l through 0 to +l, it prescribe sthe orientation fo the orbital in teh space around the nucleus.

Front 48

levels(shells)

Back 48

given by the n value, teh smaller the n value, the lower the energy level and the greater the probability of the electron being closer to the nucleus.

Front 49

sublevels(subshells)

Back 49

the atom's levels contain these, designate the orbital shape(s, p, d, f)

Front 50

orbital

Back 50

each allowed combination of n, l, ml values specifies one of the atom's...the three quantum numbers describe its size(energy), shape, and spatial orientation

Front 51

s orbital

Back 51

an orbital with l=0 as a spherical shape with the nucleus at its center

Front 52

node

Back 52

a shell-like region where the probability drops to zero.

Front 53

p orbital

Back 53

an orbital with l=1, has two regions(lobes) of high probability, one on either side of the nucleus.

Front 54

d orbital

Back 54

l=2, can have five different orientations.

Front 55

f orbital

Back 55

l=3, must have a principal quantum number of at least n=4