Test 1 Flashcards
1
Q
Wavelength
A
- distance between 2 peaks or 2 troughs
2
Q
frequency
A
number of waves per second that pass through a given point
3
Q
electromagnetic spectrum
A
- complete range of all types of radiation that has both electric and magnetic fields that travels in waves ADD PICTURE
- as frequency increases, wavelength decreases
- as frequency decreases, wavelength increases
4
Q
amplitude
A
- height of a wave
- related to energy (intensity) of light; greater amplitude=brighter
5
Q
wave interferences
A
- diffraction
- constructive
- destructive
6
Q
diffracton
A
process of light bending around an obstacle or spreading out after it moves through a small space
7
Q
constructive
A
when two waves overlap in such a way that they combine to make a larger wave
8
Q
destructive interference
A
two waves overlap in a way they cancel eachother out
9
Q
light
A
comes in “packets” (particles) of energy; photons
10
Q
Photoelectric effect
A
- to eject an electron from the metal, minimum frequency of light is needed
- above minimum frequency, kinetic energy of the ejected electron increases with light frequency
- above minimum frequency increases light intensity increases the number of ejected electrons but not their kinetic energy
11
Q
wave particle duality
A
light: both wave and particulate character
matter: both particulate and wave characteristics
12
Q
shrödinger model
A
matter has wave characteristics as well as particle characteristics
13
Q
principle quantum number
A
size of the orbital, positive integer
14
Q
angular momentum quantum number
A
shape of the orbital, n-1
15
Q
magnetic quantum number
A
orientation of the orbit, -l, l-1, l+1, +l
16
Q
orbital forms
A
17
Q
electron-nucleus attractions
A
Electrons are negatively charged and are pulled pretty close to each other by their attraction to the positive charge of a nucleus
18
Q
electron-electron repulsions
A
electrons further from the nucleus are shielded from full +ve nuclear charge by electrons closer to the nucleus
19
Q
effective nuclear charge
A
Zeff+ Zactual - electron shielding
20
Q
matter
A
both wave and particle properties
21
Q
quantum mechanics
A
gives electron configuration of atoms which helps us understand their properties
22
Q
why do bonds form
A
because molecule has a lower energy than its separated atoms
23
Q
ionic bonding
A
- electrostatic forces of attraction between oppositely charged ions
- no sharing of electrons
- EN difference > 2
24
Q
covalent bonding
A
- electrons shared between atoms of non-metals
- atoms are NOT shared equally
- EN difference < 2
25
electronegativity
- the ability of an atom in a molecule to attract electrons towards itself
- difference in electronegativity of an atom leads to a polar covalent bond
26
nonpolar covalent
EN difference = 0
27
lewis structure
- a representation of covalently bonded molecules
28
VSEPR
- Valence Shell Electron-Pair Model
- observed shapes of molecule arise from each electron group around an atom arranging themselves as far away as possible from other electron groups to minimize repulsions between them
29
electron group
single bond, multiple bond, or lone pair
30
Linear
2 e- groups
31
tetrahedral
4e- groups
32
octahedral
6e- group
33
triagonal planar
3e- groups
34
trigonal bipyramidal
5e- groups
35
dipole moment
a meausre of the separation of charge in a molecule arising from the unequal sharing of electrons in polar bonds
35
intramolecular forces
- covalent bonding
- much stronger
36
intermolecular forces
- much weaker than intramolecular
- important for state of matter, solubility, boiling point, melting point, etc.
37
ion-dipole interaction
- interaction between fully charged ion and partial charges of a polar molecule
- the energy of attraction increases with the charge of the ion and decreases witht he square of the distance between the ion and dipole
- polar molecules orient towards ions that the positive end of the dipole is near the anion and the negative is near the cation
38
dipole dipole
- polar molecules attract one another when they orient with unlike charges close together but repel one another when they orient with like charges together
39
hydrogen bonding
- dipole dipole interactions between h and very electronegative elements N, O and F
40
london dispersion forces
- moving electrons randomly concentrate more in one region than another
- an atoms electron cloud is polarizable: susceptible to distortion by neighbouring charge, increases with the number of electrons which increases with molecular mass
41
Comparison of intermolecular forces
(highest to lowest)
ion-dipole
hydrogen bonding
dipole-dipole
ldf
42
kinetic molecular theory "ideal gas"
1. gases made of tiny particles moving completely randomly
2. total volume of particles very small compared to size of container
3. particles do not interact with eachother (low imf)
4. particle collisions are elastic (no energy lost)
5. kinetic energy (KE) increases with temperature
43
pressure
results from gas particles colliding with container walls
43
effusion
escape of a gas throigh a hole into a vacuum
43
diffusion
movement of one gas through another
43
crystalline solids
- well ordered matter within the solid
- arrangement of atoms in the solid repeats itself
44
amorphous solids
dont have extensive ordering of particles
44
molecular solids
Molecules held together by intermolecular forces, relatively low melting points
45
covalent network solids
extended structures of atoms held together by covalent bonds, very high melting points
46
allotropes
different structural forms of an element
47
metallic solids
"metallic bonding" between atoms= metal atoms as cations in a sea of "delocalized electrons", high conductivity, malleable and ductile
48
ionic solids
held together by electrostatic attraction, high melting points
49
liquids
most liquids are molecular, intermolecular forces keep particles close together but mot stron enough to keep particles from moving past eachother
50
surface tension
amount of energy required to expand a liquid surface
51
capillary action
rising of a liquid in a narrow space against the pull of gravity
52
cohesive forces
between molecules
53
adhesive forces
between molecules and a containers wall
54
endothermic
absorbs heat and cools the surroundings
55
exothermic
process releases heat, causing the temperature of the immediate surroundings to rise
56
what increases boiling point
higher intermolecular forces
57
vapour pressure
- the pressure of gas in equilibrium (co-existing) with its liquid/solid at a specified temperature
- depends on strength of intermolecular forces
- greater intermolecular forces= fewer molecules escape liquid and need more KE to overcome
58
boiling points
- temperature at which vapour pressure of a liquid equals the external pressure
- enough kinetic energy to vapourize against external pressure; water can form vapour bubbles within
59
solutions
- one or more substance (solutes) mixed at the molecular level (dissolved) in a medium (solvent (usually liquid))
- can vary in amount of solute
60
solute
strong ionic lattice - attraction of + and -
61
solvent
h-bonding between H2O molecules
62
colligative properties
solution properties that depend on concentration of solute, not its identity
63
freezing point depression
dolutes lower freezing point of the solvent
64
boiling point elevation
solutes raise boiling point of the solvent
65
vapour pressure lowering
- solutes decrease vapour pressure of the solvent
- non-volatile solutes decrease vapout pressure of solvent
66
osmotic pressure
pressure that must be applied to a solution to prevent osmosis from a sample of pure solvent
67
non-volatile
does not enter gas phase, no vapour pressure
68
volatile solution
both solvent and solute contribute to vapoir pressire
69
osmosis
net flow of solvent through a semi-permeable membrane from a dilute solution to more concentrated solution
