Exam #1 Flashcards
1
Q
What defines an element?
A
the # of protons
2
Q
Electrons
A
- outside part of the atom
- negative charge
- effectively massless
3
Q
Protons
A
- inside the nucleus
- positive charge
- # determines identity of the element
4
Q
changing # of neutrons
A
isotope
5
Q
changing # of electrons
A
ion
6
Q
changing # of protons
A
different element
7
Q
Isotope Facts
A
- named after the mass #
- quantity vary among the elements
- mass # in periodic table is the weighted average of isotope masses
8
Q
Ions
A
the same element (same # of protons), different # of electrons, has a net electrical charge
9
Q
Anions
A
when atoms GAIN electrons, overall negative charge
10
Q
Cations
A
when atoms LOSE electrons, overall positive charge
11
Q
How to find the # of electrons
A
- if the net charge is 0, then the # of electrons = # of protons
- if ion is positively charged, proton # - charge #
- if ion is negatively charged, proton # + charge #
12
Q
wavelength (λ)
A
the distance between corresponding points of a wave
13
Q
frequency (u)
A
of wave cycles per unit time
14
Q
What is the general relationship between frequency & wavelength?
A
- as wavelength gets longer, frequency decreases
- as wavelength gets shorter, frequency increases
- INVERSELY RELATED
15
Q
Relationship of Energy (E)
A
- directly proportional to frequency
- inversely proportional to wavelength
16
Q
Reason for unique emission spectra for each element
A
the distinct arrangement and # of electrons in its atoms
17
Q
Bohr Model of H Atoms
A
- there are certain energy levels that an electron can occupy
- the more energy levels fallen, the more energy emitted
18
Q
Absorb
A
lower → higher
19
Q
Emit
A
higher → lower
20
Q
Problems with Bohr Theory
A
- it only works for hydrogen
21
Q
Bohr Theory was the first to…
A
- indicate that electrons occupy various energy levels
- indicate that electrons could transfer between energy levels
22
Q
Location of metals
A
left side of periodic table
23
Q
Location of metalloids
A
middle right of periodic table
24
Q
Location of nonmetals
A
right side of periodic table, except hydrogen
25
Metal characteristics
ductile, conductive, shiny, malleable, all solid except mercury
26
Nonmetal characteristics
poor conductors of heat & electricity, brittle, can be all 3 states of matter
27
Metalloid characteristics
typically appear shiny, brittle, semi conductors, good conductors
28
Periods
horizontal rows, exhibit trends
29
Groups
vertical columns, similar properties
30
Group 1
Alkali Metals
31
Group 2
Alkali Earth metals
32
Group 3
Icosagens
33
Group 4
Crystallogens
34
Group 5
Phlctogens
35
Group 6
Chalcogens
36
Group 7
Halogens
37
Group 8
Noble gases
38
Alkali metal characteristics
soft, low melting points, low density, very reactive
39
Alkali earth metal characteristics
harder, higher melting, denser than alkali metals, reactive but less than alkali metals
40
Halogen characteristics
nonmetals, diatomic, F2 & Cl2 are gases, Br2 is liquid, I2 is solid, very reactive
41
Noble gas characteristics
all gases are at room temp, very low melting & boiling points, very unreactive, lack strength
42
Ionic
1 metal & 1 nonmetal, electrons are lost & gained to make ions which are then attracted to each other
43
Covalent or Molecular
2 nonmetals, electrons are shared
44
Wave particle duality
an electron can be described as both a particle & a wave
45
Heisenberg Uncertainty Principle
we cannot know both the position & speed of a particle (such as a photon or electron) with perfect accuracy
46
Determinancy
definite, can be precisely determined
47
Indeterminacy
uncertain, cannot. be definitively known
48
Orbits
fixed path where electrons revolve around the atom's nucleus
49
Orbitals
an area used to calculate the probability of finding any electron
50
Schrödinger Equation
describes the form of probability waves, leads to quantum numbers
51
Principle quantum number (n)
integer that determines overall size & energy for an orbital, L & mL are based on n
52
Angular momentum quantum number (L)
determines the shape and name of the orbital
53
Magnetic quantum number (mL)
determines orientation of orbital in space, mL is equal to the set of possible integers from -L to +L, # of solutions of mL are equal to the # of possible orientations of an orbital
54
Spin Quantum number (mS)
determines the spin of the electron, not dependent on the other numbers, mS is either -1/2 or +1/2
55
Pauli Exclusion Principle
no 2 electrons can have the same 4 quantum numbers
56
Aufbau Principle
fill the lowest energy levels with electrons first
57
Hund's Rule
fill lower energy levels first singly with parallel spins
58
Valence electrons
- participate in chemical bonding
- for main group elements (s & p orbitals)
- outermost shell (principal energy levels)
59
Core electrons
- do NOT participate in chemical bonding
- in complete principal energy level (previous noble gas)
- in d & f orbitals
60
dots in lewis dot structures represent...
valence electrons
61
when are lewis dot structures useful?
when drawing covalent compounds
62
how many electrons in each "box" of lewis dot structures?
2
63
each line in a lewis dot structure represents...
a covalent bond
64
guidelines for lewis dot structures for covalent compounds
1. count total valence electrons
2. create skeleton structure
3. drawing single bonds to connect outer atoms to central atom
4. check your work
