Gen Chem Atoms and Period Trends (1)

Question 1

Alpha decay

Answer 1

an atom releasing an alpha particle (He atom); mass change of 4, nucleus change of -2 (loss of two protons and two neutrons)

Question 2

Atomic number

Answer 2

number of protons in an atom

Question 3

Atomic radius

Answer 3

distance from the center of an atom to the edge of its electron cloud

Question 4

Atomic weight

Answer 4

weighted average of all naturally occurring isotopes of an atom with respect to their naturally occurring quantities

Question 5

Beta decay

Answer 5

an atom releases a beta particle; takes the form of an electron or a positron; no change in mass, change in charge -1 or +1

Question 6

Bohr model

Answer 6

explains that electrons move around protons (nucleons) in an atom in discrete circular paths (orbitals) dependent on their energy levels

Question 7

Diamagnetic

Answer 7

all electrons in an atom exist in pairs in their respective orbitals; do not strongly interact with magnets

Question 8

Effective nuclear charge

Answer 8

a measure of the net positive charge that electrons in an atom feel

Question 9

Electron

Answer 9

subatomic particle with a charge of -1 and negligible mass

Question 10

Electron affinity

Answer 10

the amount of energy released by an electron when it attracts an electron

Question 11

Electron/positron capture

Answer 11

results in one fewer proton when an atom captures a positron

Question 12

Electron configuration

Answer 12

conventional nomenclature for electronic structure

Question 13

Electronegativity

Answer 13

attractive force an atom exerts to attract an electron

Question 14

Emission spectrum

Answer 14

characteristic wavelength emitted by an atom

Question 15

Excited state

Answer 15

when electrons jump to a higher orbital level after absorbing energy equal to or greater than the energy of the higher orbital

Question 16

Gamma decay

Answer 16

when an atom releases a gamma particle

Question 17

Ground state

Answer 17

when all electrons of an atom are in the lowest possible orbitals

Question 18

Group

Answer 18

columns of the period table; elements in the same group share chemical properties

Question 19

Half life

Answer 19

the time it takes an atom to decay half its original mass

Question 20

Hund’s rule

Answer 20

each orbital must be occupied by a single electron before the orbital is occupied by two electrons of opposite spins

Question 21

Ionization energy

Answer 21

amount of energy needed to remove an electron from the valence shell of an atom

Question 22

Isotope

Answer 22

atoms of the same element that contain differing numbers of neutrons

Question 23

Mass number

Answer 23

protons + neutrons

Question 24

Neutron

Answer 24

subatomic particle with a 0 charge and a mass of 1 amu

Question 25

Paramagnetism

Answer 25

refers to atoms that have unpaired electrons; strongly attracted to magnets

Question 26

Pauli exclusion principle

Answer 26

states that no two electrons can contain the same 4 quantum numbers

Question 27

Planck’s constaant

Answer 27

a constant represented by h (h=6.626x10^-34 m^2kg/sec); always given

Question 28

Proton

Answer 28

subatomic particle with a positive charge and a mass of 1 amu

Question 29

Quantum numbers

Answer 29

system to describe an electron in an atom with 4 quantum numbers - n, m, ml and ms

Question 30

Strong nuclear force

Answer 30

an attractive force that holds protons and neutrons together

Question 31

Subatomic particles

Answer 31

protons, neutrons and electrons that make up an atom

Question 32

Valence electrons

Answer 32

electrons in the outermost electron shell of an atom