Chemistry Test 4

Question 1

Smallest particle of an element capable of chemical interactions

Answer 1

atom

Question 2

Chemical compounds are composed of a fixed ratio of elements as determined by mass; there are always 2 hydrogens for 1 oxygen in a water molecule

Answer 2

law of definite proportions

Question 3

streams of electrons that are produced when a high voltage is applied to electrodes in an evacuated tube; used by J.J. Thomson to find that every atom has small, negatively charged particles

Answer 3

cathode rays

Question 4

A subatomic particle that has a negative charge; found outside the nucleus; has the least mass

Answer 4

electron

Question 5

the center of an atom, which contains the protons and neutrons

Answer 5

nucleus

Question 6

A subatomic particle that has a positive charge and that is found in the nucleus of an atom; aka atomic number; discovered by Ernest Rutherford

Answer 6

proton

Question 7

the number of protons in the nucleus of an atom

Answer 7

atomic number (z)

Question 8

A subatomic particle that has no charge and that is found in the nucleus of an atom; discovered by James Chadwick

Answer 8

neutron

Question 9

the major energy levels of an atom (1-7); shells; first quantum number

Answer 9

principal energy level (n)

Question 10

The lowest energy state of an atom

Answer 10

ground state

Question 11

a packet of electromagnetic energy

Answer 11

photon

Question 12

matter (including electrons) can be thought of as having properties of both a particle and a wave

Answer 12

Louis de Broglie

Question 13

it is impossible to know exactly both the velocity and the position of a particle at the same time

Answer 13

Heisenberg uncertainty principle

Question 14

a diagramic representation that uses dashes and arrows to show the principal energy levels and sublevels for all the electrons in an atom

Answer 14

orbital notation

Question 15

Describes the subshell in which an electron is found; s, p, d, f

Answer 15

azimuthal quantum number (l)

Question 16

the orientation of an orbital around the nucleus

Answer 16

magnetic quantum number (m)

Question 17

The number that describes the two possible “spin” states of a pair of electrons in an orbital.

Answer 17

electron spin quantum number

Question 18

two electrons in the same orbital must have opposite spins

Answer 18

Pauli exclusion principle

Question 19

states that electrons must fill the lowest available energy sublevel before any can be placed in higher energy levels

Answer 19

Aufbau principle

Question 20

the arrangement of electrons in an atom

Answer 20

electron configuration

Question 21

electrons occupy orbitals of the same energy in a way that makes the number of electrons with the same spin direction as large as possible; describes how electrons fill orbitals

Answer 21

Hund’s rule

Question 22

Atoms of the same element that have the same number of protons, but different numbers of neutrons

Answer 22

isotope

Question 23

the sum of the number of neutrons and protons in the nucleus

Answer 23

mass number (A)

Question 24

The representation of a specific isotope. The atomic number is listed below the symbol, the mass number above.

Answer 24

isotope notation

Question 25

alternative unit equivalent to the atomic mass unit

Answer 25

unified atomic mass unit (u)

Question 26

Electrons on the outermost energy level of an atom

Answer 26

valence electron

Question 27

an electron-configuration notation in which only the valence electrons of an atom of a particular element are shown, indicated by dots placed around the element's symbol

Answer 27

electron dot notation

Question 28

A positively charged ion

Answer 28

cation

Question 29

A negatively charged ion

Answer 29

anion

Question 30

sublevel s can hold

Answer 30

2 electrons

Question 31

sublevel p can hold

Answer 31

6 electrons

Question 32

sublevel d can hold

Answer 32

10 electrons

Question 33

sublevel f can hold

Answer 33

14 electrons

Question 34

The modern periodic table is a model representing

Answer 34

principal energy levels and energy sublevels

Question 35

T/F The general region of space where an electron is most probably found is known as an orbital.

Answer 35

True

Question 36

T/F Neutrons contribute to an atom's mass and its shape

Answer 36

False

Question 37

T/F An atom that gains three electrons will have a +3 charge

Answer 37

False

Question 38

T/F Electron dot notation is a shorthand way of showing valence electrons.

Answer 38

True

Question 38

T/F Each atom can be identified by the number of protons in its nucleus

Answer 38

True

Question 39

T/F No orbital can hold more than two electrons.

Answer 39

True

Question 40

T/F An electron can behave only as a wave.

Answer 40

False

Question 41

T/F The first quantum number identifies the principal energy level of an atom.

Answer 41

True

Question 42

T/F Scientific models are working representations of experimental facts that have been proven to be correct in all cases.

Answer 42

False

Question 43

determined by the weighted averages of isotopes of an element

Answer 43

Atomic mass

Question 44

Energy shells are also called

Answer 44

Energy levels

Question 45

The highest number of energy levels that atoms can have at ground state

Answer 45

7

Question 46

Philosophical atomism is a natural philosophy that proposes the universe is made up of indivisible particles called atoms. (Who discovered this?)

Answer 46

Democritus

Question 47

first experimental atomic model

Answer 47

John Dalton

Question 48

used the cathode ray tube to discover electrons; plum pudding model

Answer 48

J.J. Thomson

Question 49

discovered x-rays

Answer 49

Wilhelm Roentgen

Question 50

Discovered the neutron

Answer 50

James Chadwick

Question 51

conducted the gold foil experiment and discovered the alpha particle

Answer 51

Hans Geiger

Question 52

said that electrons are in energy levels; developed the planetary model

Answer 52

Niels Bohr