General Chemistry The Molecular Science Ch.7

Front 1

Valance Electrons

Back 1

electrons in the outermost shell, which are the chief factor in chemical reactivity

Front 2

Electromagnetic Radiation

Back 2

consists of oscillating perpendicular electric and magnetic fields that travel through space and time at the same rate( speed of light in a vaccum is 186,000 miles/second or 2.998 X 10 to the eigth m/s)

Front 3

Spectrum

Back 3

the distribution of intensities of wavelengths or frequencies of electromagnetic radiation emitted or absorbed by an object.

Front 4

Wavelength

Back 4

the distance between adjacent crests (or troughs) in a wave

Front 5

Frequency

Back 5

the number of complete waves passing a point in a given period of time...cycles per second

Front 6

Hertz

Back 6

S to the negitive first

Front 7

Intensity of Radiation

Back 7

Brightness of the visable light; positive correlation to amplitude

Front 8

Amplitude

Back 8

Height of the Wave Crest; positive correlation to Intensity of Radiation

Front 9

Relationship of frequency of electromagnetic radiation to wavelength

Back 9

wavelength X Frequency = speed of light (2.998E8)

Front 10

Examples of radiation with shorter visable wavelengths

Back 10

Ultraviolet radiation (sunburn type), X-rays, and Gamma rays (emitted in the process of radioactive disintegration of some atoms.) These types are visable to the naked eye.

Front 11

In order of wavelength, not visible to the naked eye.

Back 11

Infrared radiation, microwave, television, radio transmissions, and celluar phones.

Front 12

A fellow student says that low frequency radiation is short wave radiation. You disagree. Explain why the other student is wrong.

Back 12

Wavelength and Frequency are directly related therefore there is a positive relationship. Short wave length would give it a higher not lower frequency because there were more waves occuring.

Front 13

The size of radio antenna is proportional to the wavelength of radiation. Cellular Phones have antennas often less than 0.076 m long, whereas submarine antennas are up to 2000 m long. Which is using higher frequency radio waves?

Back 13

The cell phone would be using a higher frequency with its shorter wavelength.

Front 14

Planck's Quantum Theroy

Back 14

An Atom when in a hot object emits radiation but in the smallest quantity possible. This smallest packet of energy is called a quantum. This packet of energy is proportional to the frequency of radiation according to the equation E(quantum)= hv(radiation). H= Planck's Constant= 6.62 X 10 to the -32nd Joules per second.

Front 15

Planck's Constant

Back 15

H= Planck's Constant= 6.62 X 10 to the -32nd Joules per second.

Front 16

In the stratosphere, ultraviolet radiation with a frequency of 1.36 X 10^-15^ hertz can break C-Cl bonds in CFCs, which can lead to stratospheric ozone depletion. Calculate the energy per quantum of this radiation.

Back 16

E=hv=(6.62 X 10^-34^ J/s)(1.36 X 10^15^ hertz)= 9.01 X 10^-19^ J

Front 17

relationship between wavelength and energy in a quantum radiation

Back 17

Quantum Radiation = Planck's Constant X the speed of light divided by wavelengthThe energy per quantum of radiation increases as the wavelength gets shorter

Front 18

Photoelectric Effect

Back 18

Certain metals emit electrons when illuminated by light of certain wavelengths. For each photosensitive metal there is a threshold wavelength below which no photoelectic effect is observed.

Front 19

Photons

Back 19

Einstein assumes Planck's Quanta are massless particles of light. These massless particles of light can knock electrons loose if their energy is greater than the electron's minimum energy. E(min)= electrons minimum energy. E= hv where E is energy, h is Planck's Constant and v is frequency.

Front 20

Duel Nature of Light

Back 20

Light appears to have both particle and Wave characteristics.

Front 21

refraction

Back 21

bending of a light prism

Front 22

Diffraction

Back 22

when light passes through adjacent slits, the waves are scattered so that emerging light waves spread out

Front 23

Continous Spectrum

Back 23

spectrum of white light, which includes light of all wavelengths in visible regions.

Front 24

Line emission spectrum

Back 24

the relative intensity of electromagnetic radiation of each frequency when it is heated, characteristic of each element

Front 25

Orbits

Back 25

the energy levels that electrons are restricted to

Front 26

Principal Quantum Number

Back 26

N, the integer each orbit is assigned, can be any number from one to infinity. The energy of the electron and the size of its orbit increases as the value of n increases.

Front 27

Any atom with its electrons arranged to give the lowest total energy is at ________.

Back 27

Ground State

Front 28

When an electron has more energy than that of ground state it is said to be in an __________.

Back 28

Excited State

Front 29

Rydberg Constant

Back 29

2.179 X10^-18^ Joules
The Rydberg Constant represents the highest wavenumber of any photon that can be emitted from the hydrogen atom or the wavenumber of the lowest energy capible of ionizing the hydrogen ion from its ground state.

Front 30

The difference in energy when an electron when it moves from its initial state to its final state can be calculated by...

Back 30

Change in E= E(final)- E(initial)

Front 31

Frequency is related to Delta E

Back 31

Frequency= Change in Energy divided by Planck's Constant