Ch 1: Atomic Structure

Question 1

atomic number

Answer 1

number of protons in a given element

Question 2

mass number

Answer 2

sum of the element’s protons and neutrons

Question 3

atomic mass

Answer 3

essentially equal to the mass number, being the sum of protons and neutrons

Question 4

isotopes

Answer 4

atoms of a given element (same atomic number) that have different mass numbers. they differ in the number of neutrons

most identified by element and mass number
ex: carbon-12

Question 5

three isotopes of hydrogen go by

Answer 5

protium
deuterium
tritium

Question 6

atomic weight

Answer 6

weighted average of the naturally occuring isotopes of an element

Periodic table lists atomic weights not atomic masses

Question 7

quantum

Answer 7

the enerrgy difference between energy levels of the revolving electrons around the nucleus in the Bohr Model of the atom

Question 8

the energy of an electron ____ the farther it is from the nucleus

Answer 8

increases

Question 9

quantization

Answer 9

there is not an infinite range of energy levels available for an electron; they can only exist at certain energy levels

Question 10

atomic emission spectrum

Answer 10

every element has s characteristic spectrum when electrons fall from excited state back to ground and sometimes the emitted corresponds to a frequency in the visible light range

Question 11

quantum mechanical model

Answer 11

says electrons do not travel in defined orbits but rather are localized in orbits; regions of space around nucleus where there is a probability of finding e-

Question 12

Heisenberg uncertainty principle

Answer 12

impossible to know both the electrons position and momentum exactly at the same time

Question 13

4 quantum numbers are

Answer 13

n, l, ml, ms

Question 14

principal quantum number (n)

Answer 14

average energy of the shell

Question 15

azimuthal quantum number (l)

Answer 15

subshells within a given principal energy levels (s,p,d, and f)

Question 16

magnetic quantum number (ml)

Answer 16

specifies particular orbital within a subshell where an electron is likely to be found at given moment in time

Question 17

spin quantum number (ms)

Answer 17

indicates the spin orientation (+/- 1/2) of an electron in an orbital

Question 18

Hund’s Rule

Answer 18

every subshell with multiple orbitals (p,d, and f) fill electrons so that every orbital in a subshell gets one electron before any get a second

Question 19

paramagnetic

Answer 19

unpaired electrons that align with magnetic fields, attracting the material to a magnent

Question 20

dimagnetic

Answer 20

all paired electrons, which cannot easily be realigned; they are repelled by magnets