GIANT FINALS STUDY SESH Flashcards
1
Q
science
A
the knowledge obtained by observing natural events and conditions in order to discover facts and formulate laws or principles that can be verified or tested
2
Q
chemistry
A
the study of the composition, structure, and properties of matter and the changes that matter undergoes
composition: what a molecule is made up of (i.e. matter, atoms)
structure: the shape that gives a molecule it’s properties
3
Q
chemical
A
any substance that has a definite composition or is used or produced in a chemical process
definite composition: ethanol
4
Q
basic vs applied research
A
basic: carried out to increase general knowledge
applied: carried out to solve practical problems
5
Q
matter vs mass
A
matter: has mass and takes up space
mass: a measure of the amount of matter
6
Q
chemical properties
A
a substance’s ability to undergo changes (a reaction) that alter its composition and identity
7
Q
element vs compound
A
element: composed of one kind of atom
compound: made from two or more elements in fixed proportions
8
Q
physical vs chemical changes
A
physical: the identity of a substance IS NOT changed
(i. e. change of state, crumbling)
chemical: the identity of a substance CHANGES
(i. e. combustion, oxidation)
9
Q
what are the three major states of matter?
A
solid, liquid, gas
10
Q
anything that happens with matter requires…
A
energy!!!
- energy accompanies both physical and chemical changes
11
Q
energy, mass, and matter are neither…
A
created nor destroyed
12
Q
mixtures vs pure substances
A
mixtures: two or more different substances joined together (not chemically)
pure substances: consisting of one element or compound
13
Q
periodic table
A
an arrangement of the elements in order of their atomic numbers so that elements with similar properties fall in the same column
- elements organized by chemical properties
- columns = groups
- rows = periods
- same periods = same outer valence shell configuration
- same groups = similar properties
s-block, p-block, d-block, and f-block
14
Q
what are the different classifications?
A
- metals: shiny, malleable, ductile, good conductors
- nonmetals: brittle, poor conductors
- metalloids: intermediate in properties between metals and nonmetals
- noble gases: unreactive
15
Q
scientific method
A
a logical approach to solving problems that lend themselves to investigation
16
Q
hypothesis vs theory
A
hypothesis: a TESTABLE statement that serves as the basis for predictions and further experiments
(if. .. then…)
theory: a broad generalization that explains a body of known facts or phenomena
- can change over time
17
Q
what is the result of nearly every measurement?
A
a number and a unit
18
Q
SI system
A
a system of measurement used in science consisting of…
- meters (length)
- kilograms (mass)
- seconds (time)
- kelvin (temperature)
- mole (amount of substance)
19
Q
weight
A
a measure of the gravitational pull on matter
20
Q
derived SI units
A
- square meter (area)
- cubic meter (volume)
21
Q
density
A
- the level of compactness of a substance
- the ration of mass to volume
- density = mass/volume
22
Q
conversion factors
A
used to convert from one unit to another
23
Q
accuracy vs precision
A
accuracy: the closeness of a measurement to the correct or accepted value
precision: the closeness of values for a set of measurements
24
Q
significant figures
A
consist of all digits known with certainty plus one final digit, which is uncertain
- answer should have the same amt of sigfigs as the number that has the fewest sigfigs
25
exact conversion factors
completely certain and do not limit the number of digits in a calculation
i.e. avogadro's number
26
directly vs inversely proportional
directly proportional: dividing one by the other yields a constant value
- increase in a = increase in b
- a/b = c
inversely proportional: their product has a constant value
- ab = c
- increase in a = decrease in b
27
history of atoms
- atoms have been around since ancient Greece
- in the 19th century, John Dalton proposed a scientific theory of atoms than can still be used to explain properties of most chemicals today
28
mass ratios
- always the same, regardless of how much of the compound there is or how it was formed
- if two or more different compounds are composed of the same two elements, then the ratio of the masses of the second element combined with a certain mass of the first element can be expressed as a ration of small whole numbers
29
cathode-ray tubes
supply evidence of the existence of electrons, which are negatively charged subatomic particles that have relatively little mass
- measured the charge-to-mass ratio of an electron
30
properties of the nucleus
- positive
- small
- dense
31
atomic nuclei
- Rutherford found evidence for the existence of the atomic nucleus by bombarding gold foil with a beam of positively charged particles
- atomic nuclei are composed of protons and electrons
- atomic nuclei have a radii of about 0.001 pm and atoms have a radii of about 40-270 pm
32
protons vs neutrons vs electrons
protons: electric charge of +1
electrons: electric charge of -1
neutrons: no electric charge
33
atomic number vs mass number
atomic number: equal to the number of protons of an atom
mass number: equal to the total number of protons and neutrons that make up the nucleus of an atom
34
unified atomic mass unit
based on the carbon-12 atom and is a unit for measuring the mass of atoms
- equals 1.660 540 x10^23
35
average atomic mass
formed by calculating the weighted average of the atomic masses of the naturally occuring isotopes of the element
36
isotopes
two of the same elements with different # of neutrons
37
avogradro's number
approx 6.022 x10^23
- a sample that countains a number of particles equal to avo's number contains a mole of those particles
38
what nature does light have?
dual wave-particle nature
39
quantum theory
electrons can exist only at specific atomic energy levels
- developed to explain observations such as photoelectric effect and the line-emission spectrum of hydrogen
- when an electron moves from one main energy level to a main energy level of lower energy, a photon is emitted. the photon's energy equals the energy difference between two levels
- when an electron moves from one main energy level to a higher main energy level, a an amount of energy is absorbed, accounting for the difference between the two levels
40
photoelectric effect
the emission of electrons from a metal when light shines on it
- proposed by my boi Albert #HeARealOne
41
hydrogen's line-emission spectrum
- investigators passed an electric current through a tube containing hydrogen gas at low pressure, producing a pink glow
- this light was shined through a prism, separating it into four colors of the visible spectrum (known as hydrogen's line-emission spectrum)
42
what nature do electrons have?
dual wave-particle nature
43
Heisenberg uncertainty principle
it is impossible to determine simultaneously the position and velocity of an electron or any other particle
44
orbital
a three-dimensional region around the nucleus that shows the region in space where an electron is most likely to be found
45
quantization of electron energies
a natural outcome of the Schrodinger wave equation, which describes the properties of an atom's electrons
46
four quantum numbers
properties of electrons in atomic orbitals
principal quantum number (n): indicates the main energy level occupied by the electrons
- n = 1, 2, 3...
angular momentum quantum number (l): indicates the shape of the orbital
- l = 0, 1, 2... (n-1)
magnetic quantum number (m sub l): indicates the orientation of an orbital around the nucleus
- ml = -1, 0, +1
spin quantum number (m sub s): has only two possible values, +1/2 or -1/2, which indicates states of an electron in an orbital
- spin/arrow going up = +1/2
- spin/arrow going down = -1/2
47
what are the three principals in which the ground-state electron configuration of an atom can be written?
Aufbau principle: an electron occupies the lowest energy orbital that can receive it
(orbitals most be filled lowest to highest)
Hund's rule: orbitals of equal energy are each occupied by one electron before any orbital is occupied by a second electron, and all electrons in singly occupied orbitals must have the same spin state
(one orbital must be added to each section before pairing)
Pauli exclusion principle: no two electrons in the same atom can have the same set of four quantum numbers
(no two electrons can be facing up or facing down)
48
what are the three different types of notation that electron configurations can be depicted by?
orbital notation: notation with lines and arrows representing electron configurations
electron-configuration notation: spaces with a lower energy level are filled first until desired element is reached
- 1s2 2p2 2p6 3p2
noble-gas notation: an outer main energy level occupied by eight electrons and abbreviated using the symbol for the noble gas in brackets
- [He] 2s2 2p4
49
periodic law
the physical and chemical properties of the elements are period functions of their atomic numbers
50
ionic vs covalent vs metallic compounds
ionic: metal & nonmetal
covalent: nonmetal & nonmetal
metallic: metal & metal
51
cations vs anions
cation: lose one electron to form positive ion
anion: gain one electron to form negative ion
52
molecular vs ionic bonds
molecular bonds: SHARE electrons
ionic bonds: transfer electrons
53
noble gases
- unique chemical stability
- highest occupied levels have an octet of electrons (ns2 np6)
- generally unreactive
54
valence electrons
electrons in an atom that are available to be lost, gained, or shared in the formation of chemical compounds
55
electron affinity, electronegativity, and ionization energy
electron affinity: the energy change that occurs when an electron is acquired by a neutral atom (energy it takes to ADD an electron)
-increases to the right and up
electronegativity: the measure of the ability of an atom in a chemical compound to attract electrons from another atom in a compound
- increases to the right and up
ionization energy: the energy required to remove one electron from a neutral atom of an element
- increases going to the right and up
56
atomic radius vs ionic radius
atomic radius: one-half of the distance between the nuclei of identical atoms that are bonded together
- decreases going to the right and up
ionic radius: the radius of a monoatomic ion in an ion crystal structure
- decreases going to the right and up
57
octet rule
many chemical compounds tend to form bonds so that each atom shares or has eight electrons in its highest occupied energy level
58
Lewis structures vs resonance structures
Lewis structures: dot notations and lone pairs surrounding the letter of an element
**between covalent bonds
resonance structures: bonding in molecules or ions that cannot be correctly represent by a single Lewis structure
(portrays both of the Lewis structures that a compound can have)
59
ionic compound
a three-dimensional network of positive and negative ions mutually attracted to one another
-harder and more brittle and have higher boiling points than materials containing only covalently bonded atoms
60
electron sea
- formed in metallic bonding
- delocalized electrons that don't belong to any one atom, move freely about a metal's network of empty atomic orbitals. these electrons form a sea of electrons around metal atoms
- gives metals their properties of high electrical and thermal conductivity, malleability, ductility, and luster
61
VESPR theory
used to predict the shapes of molecules based on the fact that electron pairs strongly repel each other
62
hybridization theory
used to predict the shapes of molecules, based on the fact that orbitals within an atom can mix to form orbitals of equal energy
63
three types of intermolecular forces
dipole-dipole: interactions between POLAR molecules; molecules attract each other from opposite sides acting at short range
London dispersion: the intermolecular attractions resulting from the constant motion of electrons and the creation of instantaneous dipoles
- these forces are on every type of element/compound
hydrogen bonding: intermolecular force in which a hydrogen atom that is bonded to a highly electronegative atom is attracted to an unshared pair of electrons of an electronegative atom in a nearby molecule
- bonds ONLY between H-F, H-O, and H-N
- i.e. water
64
polar vs nonpolar molecules
polar: molecules with uneven Lewis structures and uneven dipoles
nonpolar: molecules with an even Lewis structure and dipoles that balance each other out
65
positive vs negative monatomic ions
positive: identified by the name of the appropriate element
negative: named by dropping parts of the ending of the element's name and adding -ide to the root
66
binary compounds
- composed of two elements
| - binary ionic compounds are named by combining the names of the positive and negative ions
67
formula mass, molar mass, and percentage composition
formula mass: sum of average atomic masses of all atoms present in the formula
molar mass: used as a conversion factor between amount in moles and mass in grams of a given compound or element
percentage composition: the percentage by mass of each element in the compound
68
empirical formula vs molecular formula
empirical: shows the SMALLEST whole-number ratio of atoms in a given compound
- indicates how many atoms of each element are combined in the simplest unit of a chemical compound
molecular: the actual formula of a molecular compound
- can be found from the empirical formula if the molar mass is measured
69
what are observations that suggest a chemical reaction is taking place?
- evolution of energy as heat and light
- production of gas
- change in color
- formation of a precipitate
70
balanced chemical equation
represents, with symbols and formulas, the identities and relative amounts of reactants and products in a chemical reaction
71
what are the four types of reactions?
synthesis: A + X --> AX
decomposition: AX --> A + X
single-displacement: A + BX --> AX + B
double displacement: AX + BY --> AY + BX
combustion: a substance combines with oxygen, releasing energy in the form of light and heat
- a hydrocarbon and oxygen yielding CO2 and H2O
72
activity series
- a list of the elements in order of their chemical reactivity
- useful in predicting whether a chemical reaction will occur
- determined through experiments
73
reaction vs composition stoichiometry
stoichiometry: element measurement
composition stoichiometry: deals with the mass relationships of elements in a compound
reaction stoichiometry: involves the mass relationship between reactants and products in a chemical reaction
74
mole ratio
the conversion factor that relates the amount in moles of any two substances in a chemical reaction
- derived from a balanced equation
75
how are the amounts vs the masses of a substance expressed?
amount of a substance: expressed in moles
mass of a substance: expressed by using mass units such as grams, kilograms, or milligrams
76
what is necessary to solve any stoichiometric problem?
- A BALANCED CHEMICAL EQUATION!!
| - the mass or amount of the reactants and products
77
limiting vs excess reactant
limiting: reactant that limits the amount of the other reactant that can combine and the amount of product that can form in a chemical reaction
- controls the maximum possible amount of product formed
excess reactant: substance that is not used up completely in a reaction
78
theoretical, actual, and percentage yields
theoretical yield: the maximum amount of product that can be produced from a given amount of reactant
actual yield: the measured amount of that product obtained from a reaction
percentage yield: the ratio of the actual yield to the theoretical yield, multiplied by 100
- actual yield/theoretical yield x 100
79
kinetic-molecular theory
- explains properties of gases, liquids, and solids
80
properties of gases, liquids, and solids relating to the kinetic-molecular theory
gases
- consisting of many tiny, fast-moving particles that are far apart relative to their size
- fluid
- high level of expansion
- low density,
- compressible
- diffuse and effuse
liquids
- particles are closer together and more ordered than those of a gas and are less ordered than those of a solid
- fairly high density
- relatively incompressible
- fluids: can flow
- can diffuse (although slower than gases)
solids
- definite volume and definite shape
- may be crystalline or amorphous
- nonfluid
- definite melting point
- very dense
- incompressible
- low rate of diffusion
81
ideal vs real gas
ideal gas: a hypothetical gas that perfectly fits all the assumptions of the kinetic-molecular theory
real gas: a gas that does not behave completely according to the assumptions of the kinetic-molecular theory
82
crystalline vs amorphous solids
crystalline solids: consisting of crystals
- exist as either a single crystal or a group of crystals
amorphous solids: atoms/particles are arranged randomly
83
crystals & crystal structures
crystal: a substance in which the particles are arranged in an orderly, geometric, repeating pattern
crystal structure: the total three-dimensional array of points that describes the arrangement of the particles of a crystal
84
surface tension vs capillary action
surface tension: a force that tends to pull adjacent parts of a liquid's surface together, thereby decreasing the surface area to the smallest possible size
capillary action: the attraction of the surface of a liquid to the surface of a solid
- happens when adhesion (water sticking to other things) is stronger than cohesion (water sticking to itself)
85
liquid-vapor equilibrium
when the molecules of a liquid in a closed system condense at the same rate at which they evaporate
86
dynamic equilibrium
when two opposing changes occur at equal rates in a closed system
87
formula unit
the simplest ratio of the compound's cations and anions
| - ionic compounds
