Chemistry Chapter 3 Quiz

Front 1

Atom

Back 1

Smallest particle of an element that retains the chemical identity of the element

Front 2

Law of constant composition

Back 2

Natural law describing the fact that a given compound always contains the same elements in the properties

Front 3

Atomic theory of matter

Back 3

Theory proposed by John Dalton stating that:
matter is composed of atoms
atoms of a given element are identical, atoms of a different element are different
atoms cannot be created nor destroyed in a chemical reaction
compounds always have the same relative ratio of atoms of different elements

Front 4

cathode ray tube

Back 4

evacuated glass tube in which a stream of electrons emitted by a cathode strikes a fluorescent material, causing it to glow

Front 5

Electron

Back 5

negatively charged particle within an atom

Front 6

Radioactivity

Back 6

spontaneous emission of radiation from an atom

Front 7

Nucleus

Back 7

concentrated core of an atom, which contains protons and neutrons

Front 8

Proton

Back 8

positively charged particle within the nucleus of an atom

Front 9

Neutron

Back 9

neutral particle within the nucleus of an atom

Front 10

Atomic mass unit

Back 10

unit by which the mass of an atom or atomic particle is expressed

Front 11

Atomic number

Back 11

number of protons in the nucleus of an atom

Front 12

Ion

Back 12

atom or group of atoms that has a positive or negative charge because it has lost or gained electrons

Front 13

Isotope

Back 13

atom that has the same number of protons as another atom, but that has a different number of neutrons

Front 14

Mass number

Back 14

sum of the number of protons and neutrons in the nucleus of a given atom

Front 15

Atomic mass

Back 15

weighted average of the masses of the existing isotopes of an element

Front 16

Nuclear reaction

Back 16

process that changes the composition of the nucleus of an atom

Front 17

Strong nuclear force

Back 17

attractive force among the particles in the nucleus of an atom

Front 18

Radioactive decay

Back 18

spontaneous breakdown of an unstable atomic nucleus, during which alpha particles, beta particles, and gamma rays may be emitted

Front 19

Nuclear equation

Back 19

equation that describes the changes that occur during radioactive decay

Front 20

Alpha radiation

Back 20

2+ particles deflected toward the negative plate

Front 21

Beta radiation

Back 21

high speed electrons deflected toward the positive plate

Front 22

Gamma radiation

Back 22

similar to x-rays and is not composed of particles

Front 23

Democritus

Back 23

the first to proposes the existence of atoms

Front 24

Antoine Lavoisier

Back 24

discovered the law of conservation of matter

Front 25

Joseph Louis Proust

Back 25

discovered the law of constant composition:
compounds always contain elements in the same proportion by mass

Front 26

John Dalton

Back 26

proposed the first atomic theory of matter using Proust's and Lavoisier's laws:
matter is composed of atoms
atoms of a given element are identical, atoms of a different element are different
atoms cannot be created nor destroyed in a chemical reaction
compounds always have the same relative ratio of atoms of different elements

Front 27

Michael Faraday

Back 27

suggested that the structure of atoms were related to electricity

Front 28

Benjamin Franklin

Back 28

discovered two electrical charges - positive and negative

Front 29

J.J. Thomson

Back 29

discovered the electron in cathode ray tube experiment:
found that electrons have a negative charge b/c they were attracted to a positive charge
electrons have mass b/c they made the paddle wheel spin
calculated the ratio of charge to mass

Front 30

Robert Millikan

Back 30

discovered the mass of a single electron by using Thomson's charge to mass ratio in an oil drop experiment
Charge of electron: 1.6 x 10^-19 Cou

Front 31

Henri Becquerel

Back 31

discovered radioactivity

Front 32

Marie and Pierre Curie

Back 32

discovered radioactive elements

Front 33

Ernest Rutherford

Back 33

discovered the positively charged nucleus using gold foil experiment

Front 34

Henry Moseley

Back 34

discovered the neutron

Front 35

Nuclear Reaction

Back 35

change in nucleus

Front 36

Strong nuclear force

Back 36

force that holds the nucleus together

Front 37

Radioactive decay

Back 37

spontaneous decay of nucleus

Front 38

Nuclear equation

Back 38

shows nuclei and particles involved in radioactive decay

Front 39

alpha radiation

Back 39

helium nucleus

least penetrating ability

Front 40

beta radiation

Back 40

electron

middle penetrating ability

Front 41

Gamma radiation

Back 41

high energy radiation

most penetrating ability

Front 42

Alpha decay

Back 42

4/2 He

Front 43

Beta decay

Back 43

0/-1 e

Front 44

Positron emission

Back 44

0/1 e

Front 45

Neutron bombardment

Back 45

1/0 n

Front 46

Alpha bombardment

Back 46

4/2 He