Chap 7 vocab Flashcards Preview

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Flashcards in Chap 7 vocab Deck (39):
1

electromagnetic radiation

Oscillating, perpendicular electric and magnetic fields moving simultaneously through space as waves manifested as visble light, x-rays, microwaves, radio waves ect

2

Frequency (v)

The number of cycles a waave undergoes per second. rated to s^-1. also Hz

3

Speed of Light (c)

A fundamental constant giving the speed at which electromagnetic radiation travels in a vacuum

4

Amplitude

the height of the crest of a wave; related to the intensity of the energy.

5

electromagnetic spectrum

the continuum of wavelengths of radiant energy.

6

infrared (IR)

The region of the electromagnetic spectrum between the microwave and visible regions.

7

Ultraviolet (UV)

Radiation in the region of the electromagnetic spectrum between the visible and x-ray regions

8

Refraction

A phenomenon in which a wave changes its speed and therefore its direction as it passes through a phase boundary into a different medium

9

Diffraction

The phenomenon in which a wave striking the edge of an object bends around it.

10

Quantum Number

A number that specifies a property of an orbital or an electron

11

Planck's constant (h)

A proportionality constant relating the energy and frequency of a photon, equal to 6.626x10^-34J(s)

12

Quantum

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

13

Photoelectric Effect

The observation that when monochromatic light of sufficient frequency shines on a meta, an electric current is produced

14

Photon

A quantum of electromagnetic radiation

15

Line spectrum

A series of separated lines of different colors representing photons whose wavelengths are characteristic of an element

16

stationary state

On of the allowable energy levels of the atom in which it does not release or absorb energy.

17

ground state

The electron configuration of an atom or ion that is lowest in energy

18

excited state

Any electron configuration of an atom or molecule other than the lowest energy state

19

spectrometry

Any instrumental technique that uses a portion of the electromagnetic spectrum to measure the atomic and molecular energy levels of a substance

20

emission spectrum

The line spectrum produced when excited atoms return to lower energy levels and emit photons characteristic of the element

21

absorption spectrum

The spectrum produced when atoms absorb specific wavelengths of incoming light and become excited from lower to higher energy levels

22

de Broglie wavelength

The wavelength of a moving particle obtained from the de Broglie equation

23

wave-particle duality

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

24

uncertainty principle

the principle stated by Werner Heisenberg that it is impossible to know simultaneously the exact position and velocity of a particle; the principle becomes important only for particles of very small mass

25

quantum mechanics

the branch of physics that examines the wave motion of objects on the atomic size

26

Schrodinger equation

An equation that describes how the electron matter-wave changes in space around the nucleus

27

atomic orbital

A mathematic expression that describes the motion of the electron's matter-wave in terms of time and position in the region of the nucleus.

28

electron density diagram

The pictorial representation for a given energy sub level of the quantity() as a function of r

29

electron cloud depiction

An imaginary representation of an electron's rapidly changing position around the nucleus over time

30

radial probability distribution plot

The graphic depiction of the total probability distribution() of an electron in the region near the nucleus.

31

probability contour

A shape that defines the volume around an atomic nucleus within which an electron spends a given percentage of its time

32

principal quantum number(n)

A positive integer that specifies the energy and relative size of an atomic orbital; a number that specifies an energy level in an atom

33

angular momentum quantum number(l)

An integer from 0 to n-1 that is related to the shape of an atomic orbital

34

magnetic quantum number(ml)

An integer from -l through 0 to l that specifies the orientation of an atomic orbital in the three dimensional space about the nucleus

35

level

A specific energy state of an atom given by the principal quantum number (n)

36

sublevel

An energy substate of an atom within a level. Given by the n and l values, the sub level designates the size and shape of the atomic orbitals

37

s orbital

An atomic orbital with l=0

38

p orbital

An atomic orbital with l=1

39

d orbital

An atomic orbital with l=2