Chemistry Unit 3

Front 1

Mater composed of

Back 1

Tiny particles called atoms

Front 2

Atoms of a given element are identical in

Back 2

identical in size, mass and other properties and are different from atoms of other elements

Front 3

Atoms cannot be created

Back 3

cannot be created destroyed or subdivided

Front 4

Atoms of different elements combine in simple whole-number ratios to form

Back 4

compounds

Front 5

In chemical reactions

Back 5

atoms of different elements can combine separate or rearrange to form new substances

Front 6

Scientist - Crookes

Back 6

Cathode Ray Tube, Negative particles of some kind exist

Front 7

J.J. Thomsom

Back 7

Cathode Ray Deflection, Mas/Charge ratio of the electron determined. Discovered electron and named it

Front 8

Robert Milikan

Back 8

Oil Drop Experiment. Charge on the electron discovered

Front 9

Ernest Rutherford
Marsden and Hans Geiger

Back 9

Gold Foil Experiment. Nucles present in atom, it is very small compared to the region containing the electrons, and it is the heaviest part of the atom. Contains + protons, 0 neutrons

Front 10

Protons are charged

Back 10

positively

Front 11

Neutrons are

Back 11

Not charge

Front 12

Electrons are

Back 12

Negatively charged

Front 13

Nucleus contains

Back 13

positive protons and neutral neutrons

Front 14

Energy levels contain

Back 14

negative electrons

Front 15

Atomic number -

Back 15

The number of protons in an atom

Front 16

Mass number -

Back 16

Sum of protons and neutrons

Front 17

Isotope -

Back 17

A different form of an element that contains a different number of neutrons but has the same atomic number (number of protons)

Front 18

Average Atomic Mass -

Back 18

The decimal number on the periodic table for that element. This is obtained by getting the weighted average of all forms of that element known to man

Front 19

Atomic Weight -

Back 19

is the weight of the element measured in grams

Front 20

The mole was discovered by

Back 20

Amedeo Avogadro

Front 21

A mole is

Back 21

a unit used to measure atoms or molecules

Front 22

Electromagnetic radiation -

Back 22

Is a form of energy that travels through space as waves at the speed of light,

Front 23

Energy occurs as

Back 23

waves

Front 24

Wavelength

Back 24

The distance from crest to crest or through to through of a wave

Front 25

Frequency

Back 25

the number of waves that pass a given point in one second

Front 26

Wavelength is represented by the symbol

Back 26

lambda its a box

Front 27

Frequency is measured in

Back 27

Hertz, Hz

Front 28

As wavelength increases,

Back 28

frequency and energy decrease

Front 29

As wavelength decreases,

Back 29

Frequency and energy increase.

Front 30

Photons are

Back 30

units of light energy

Front 31

Photosynthesis is a

Back 31

chemical process that occurs in nature when sunlight strikes the chlorophyll in plants, converting it to energy

Front 32

Bohr suggested that electrons were

Back 32

particles

Front 33

Debroglie suggested that electrons also have

Back 33

wave-like characteristics

Front 34

Schordinger develloped

Back 34

developed this idea and solved wave equations to make predictions about the location of electrons in an atom

Front 35

Bohr's Model

Back 35

The nucleus contains protons and neutrons surrounded by electrons in fixed orbits.

Front 36

Ground state is

Back 36

the most stable state of that element

Front 37

Excited State is

Back 37

is when the electrons are energized, move out of their normal energy levels, return to that level, and in the process give off light, heat and/or energy.

Front 38

Radioactivity

Back 38

The spontaneous decay of certain atoms with the release of energy in the form of alpha, beta, and gamma particles.

Front 39

Radation comes

Back 39

from the nucleus of an atom

Front 40

All atoms that have an atomic number of 84 or greater are

Back 40

unstable

Front 41

All atoms that have an atomic number of 83 or below are

Back 41

stable

Front 42

Half-Life is

Back 42

the amount of time it takes for your beginning amount of material to halve itself.

Front 43

Nuclear Fisson is the

Back 43

process of heavy nuclei capturing neutrons, splitting it to form other smaller nuclei and releasing more neutrons. * Large amount of energy can be released and if not controlled a chain reaction can occur.

Front 44

Nucleas-Fusion is the

Back 44

combining of smaller nuclei into larger ones with the release of energy.

Front 45

Fusion occurs in the

Back 45

sun

Front 46

Which is harder to perform, nuclear fission or nuclear fusion?

Back 46

Nuclear Fusion