Final Exam Flashcards
Tera
10^12
Giga
10^9
Mega
10^6
Kilo
10^3
Deci
10^-1
Centi
10^-2
Milli
10^-3
Micro
10^-6
Nano
10^-9
Pico
10^-12
Scientific Notation
Coefficient * (10^exponent)
Kelvin
Celcius + 273.15
Fahrenheit
(9/5) + 32
Nonzeroes
Always count
Leading Zeroes
Never count
Interior Zeroes
Always count
Trailing Zeroes
Only count if…
* After a decimal
* Before a decimal, after a nonzero
Exact Numbers
Always count
Accuracy
Agreement of measured to true value
Precision
Reproducibility
Density
mass / volume
Intensive Properties
Independent of amount
Extensive Properties
Dependent of amount
Dimensional Analysis
given * (desired/given) = given
Element
Same atoms
Compound
Different atoms
Homogenous Mixture
Uniform throughout
Heterogenous Mixture
Separable mixture
Scientific Theory
- Observation
- Hypothesis
- Experiment
- Theory (model)
- Scientific Law
Scientific Law
What? (summarizes observation)
Theory
Why? (interpretation)
Conservation of Mass
“Matter is neither created nor destroyed”
Definite Proportions
Constant composition
Multiple Proportions
- When two elements form two different compounds, the masses of element B combine with 1 gram of element A
- Can be expressed as a ratio of small whole numbers
Dalton’s Atomic Theory
- Each element has atoms
- Atoms of an element have the same mass
- Atoms combine in ratios to form compounds
- Atoms cannot become other elements
J.J. Thomson
- Cathode ray experiment
- Plum pudding model
Thomson’s Conclusions
- All atoms have electrons
- Atoms contain a positive charge
- Charge to mass ratio of electrons
Rutherford
- Alpha particles sent at gold foil
- Nuclear theory atomic model
Rutherford’s Conclusions
- Dense positive core (nucleus)
- Open space where electrons are dispersed
- Atoms is electrically neutral (# electrons = # protons)
- Atom has additional mass
Millikan
Oil drop experiment
Millikan’s Conclusions
- Electron charge: -1.6*10^-19 C
- Electron mass: 9.10*10^-28 g
Plum Pudding Model
Electrons in a sphere of positive charge
Proton
- Large
- Positive charge
- Nucleus
Neutron
- Large
- Neutral charge
- Nucleus
Electron
- Small
- Negative charge
- Electron cloud
Isotope
Same number of protons, different number of neutrons
Atomic Mass Number
Total number of protons and neutrons present
Atomic Number
Number of protons
Atomic Weight
Mass of a single atom
Cation
- Positively charged
- Loss of electrons
Anion
- Negatively charged
- Gain of electrons
Mole
1 mol = 6.02214 * 10^23 units (Avogadro’s Number)
Energy
The ability to do work
Frequency
Number of cycles per second
Wavelength
Distance from crest to crest
Electromagnetic radiation from lowest to highest?
- Radio
- Microwave
- Infrared
- Visible
- Ultraviolet
- X ray
- Gamma ray
Quantum
Energy “packet”
Photon
Quantum of electromagnetic radiation
Photoelectric Effect
Emission of electrons from a material
Atomic Theory
Matter is composed of particles (atoms)
Dual Nature of Light
Light is both a wave and a particle (photon)
Bohr’s Model
Derived energy levels available to the electrons in the hydrogen atom
Principal Quantum Number
- N
- Size and energy
- Shell, principal level
Ground State
- Lowest level
- Formed by releasing energy (emission spectra)
Excited State
- Any level above ground state
- Formed by absorbing energy
Emission Spectra of Hydrogen
- Distinct, colored lines when viewed through a prism, representing specific wavelengths of light
- Emitted by excited hydrogen atoms
- As their electrons transition from higher to lower energy levels
Absorption Spectra of Hydrogen
Results of emission spectra interaction
DeBroglie Wavelength
- γ = h / mv
- All matter has duality
Heisenberg Uncertainty Principle
Δx = Δ(mv) ≥ h / 4π
Complementary Properties
Exclude one another
Determinacy
Definite predictable future
Indeterminacy
Can only predict future using probability
Angular Momentum Quantum Number
- L
- Shape
- Subshell, Sublevel
- Probability distribution (nodes = 0)
Magnetic Quantum Number
- M(l)
- Orientation
- -1 … 0 … +1
Electron Spin Quantum Number
- Ms
- Spin direction
- +1/2 (up) and -1/2 (down)
- Must be opposite
S orbital
- Spherical
- Lowest
- 1 per level
- Gets larger with energy
- No phase
P Orbital
- Peanut/Dumbbell
- Nodes separate lobes
- Has phase
D Orbital
Four-leaf clover
F Orbital
Tetrahedral
Dimitri Mendeleev
- Ordered elements by atomic weight
- Columns: similar properties
Metals
Lose electrons to form cations
Nonmetals
Gain electrons to form anions
Metalloids
- Metallic / nonmetallic behavior
- Forms cations / anions
Pauli Exclusion Principle
No two electrons can have the same four quantum numbers
Shielding
- Outer electrons repelled by core electrons
- Nuclear charge decreases
Penetration
Ability of an electron to get closer to the nucleus
Effective nuclear charge
Zeff = Z - S
Noble Gas
- Full shell
- Stable
- Nonreactive
Alkali Metals
- Lose one electron
- Cation (+1)
Alkaline Earth Metals
- Lose two electrons
- Cation (+2)
Transition Metals
Lose electrons to form cations
P Block Metals
Lose P shell and S shell to form cations
Halogens
- Metals: gain one electron to form anions
- Nonmetals: share electrons
Hund’s Rule
Electrons fill singly before being paired (degenerate)
Degenerate Orbitals
Same energy level but differ in spatial orientation
Valence Electrons
Electrons in the outermost shell of an atom
Monoatomic Ion
A charged single atom with a different number of electrons and protons
Atomic Radius
Average bonding radii
Atomic Radius Trends
- Decreases across rows
- Increases down groups
Ionic Radius
- Cations are small
- Anions are large
Ionization Energy
Energy required to remove an electron
Ionization Energy Trend
- Increases across rows
- Decreases down groups
Electron Affinity
The amount of energy released when an electron attaches to a gas
Electron Affinity Trend
- Increases across rows
- Decreases down groups
Paramagnetic
- Unpaired electrons
- Weakly attracted to magnetic fields
Diamagnetic
- Paired electrons
- Slightly repelled to magnetic fields
Ionic Bond
- Cations and anions
- Metal and nonmetal
- Complete transfer of electrons
- Lewis model
- Energy released to form crystal lattices
Covalent Bond
- Sharing 2 electrons
- Molecular compounds
- Lewis structure
Structural Formulas
- Lewis structures
- Shows structure
- Most informative
Molecular Formulas
Actual numbers and types of atoms