Vocabulary Flashcards
Law of Definite Composition/Proportions
compounds are made by combining atoms of two or more elements in a definite proportion or ratio by mass
physical properties
observed with senses; physical state, color, odor, solubility in water, density, melting point, taste, boiling point, hardness
chemical properties
can be observed in regard to whether or not a substance changes chemically; result of reacting with other substances; Ex: iron rusting, nitrogen not burning, gold not rusting, sodium and water react, silver and water don’t react, water can be decomposed by electric current
Law of Conservation of Mass
mass of reactants equals mass of products
Law of Conservation of Energy
energy is neither gained nor lost in physical or chemical changes
Law of Conservation of Mass and Energy
mass and energy are interchangeable under special conditions
Kelvin and Celsius
K = C + 273 C = K - 273
Joule and calorie
1 calorie = 4.18 joules
accuracy
how close you have come to the true value
precision
how repeatable the results are
+/- Sig figs
to the least common place
Mult or Div Sig Figs
least amount
Example of Sig Figs
- all digits except zero
- zeros between nonzero digits
- zeros to the right of the decimal point
Dalton’s Atomic Theory
Matter = small particles called atoms
atoms of an element have similar weight different than other elements
atoms cannot be subdivided, created, or destroyed
atoms of diff elements combine in simple whole number ratios to form chemical compounds
chemical rections: atoms are combined, separated, or rearranged
J.J. Thompson
electron
Rutherford
protons
James Chadwick
neutrons
Niels Bohr
orbitals/energy levels
Henry Moseley
atomic numbers; periodic law: properties of elements are periodic functions of their atomic numbers
isotopes
same number of protons; diff masses bc of neutrons
Heisenberg uncertainty principle
it’s impossible to know both the precise location and precise velocity of a subatomic
Pauli Exclusion Principle
No two electrons can have the same four quantum numbers
Aufbau Principle
an electron occupies the lowest energy orbital that can receive it
Hund’s Rule of Maximum Multiplicity
pairing will occur with the addition of one more electron to each orbital
Periodic Table Properties
acid properties increase ——>
ionization energy increases ——>
nonmetallic props increase —–>
electronegativity —–>
radioactive emissions
- alpha ray: +
- beta ray: - and high speed
- gamma ray: no charge
half-life
time required for half of the atoms or a radioactive nuclide to decay; carbon-14 has a half life of about 5,700 years
ionic bonds
- greater than 1.7
- metal and a nonmetal or polyatomic
- high melting point
- won’t conduct electricity
covalent bonds
- diatomic
- less than .4 is non polar
- greater than .4 is polar
metallic bonds
- “sea of electrons”
- metal and a metal
Intermolecular forces
(in order from strong to weak)
- hydrogen bonds
- dipole-dipole interaction
- dipole induced interaction
- London/Dispersion forces
resonance
a hybrid of the possible drawings bc no one lewis structure can represent the situation
VSEPR theory
valence shell electron pair repulsion; bond angles
Hybridization theory
changes in the orbitals of the valence electrons
Hybrid Arrangements
- linear: 180; two atoms bonded to center
- bent: 2 atoms bonded and 1 or 2 lone pairs (water 105 degree angle)
- trigonal planar: 120; 3 atoms bonded to center
- tetrahedral: 4 atoms bonded to center
- trigonal pyramidal: 3 atoms bonded to center and 1 lone pair
- trigonal bipyramidal: 90 and 120; 5 atoms to center
- octahedral: six electron to center
Hybrid Orbitals
- sp: 180/linear
- sp2: 120
- sp3: example is ammonia
- sp3d2: hybrid of an s and a p electron promoted to d orbitals and transformed into six equal sp3d2 orbitals
Acid Naming Rules
- “ic” acids form “ate” salts
- “ous” acids form “ite” salts
- “hydro…ic” acids form “ide” salts
Law of Definite Composition
each unit of an element has the same atomic mass and every time the particular compound forms, it forms in the same percent composition
Law of Multiple Proportions
some compounds form where the mass of one element stays the same but the mass of the other varies
Activity of Metals
- potassium, calcium, sodium (in cold water)
- low to high: hydrogen, {tin, iron, zinc, aluminum} in most dilute solutions, magnesium in hot water
- {sodium, calcium, potassium} in cold water
Standards
- 760 mmHg = 760 torr = 1 atm = 101.325 kPa
- 273 K = 0C
Kinetic Molecular Theory
- matter is composed of tiny particles
- particles of matter are in constant motion
- when particles collide, there is no loss of energy
Graham’s Law of Effusion (Diffusion)
The rate of a gas is inversely proportional to the square root of its molecular mass
Charles’s Law
V₁T₁=V₂T₂ where the pressure is constant and the volume and temp vary directly
Boyle’s Law
P₁V₁=P₂V₂ where the temp is constant and the volume and pressure vary inversely
Combined Gas Law
P₁V₁/T₁=P₂V₂/T₂
Gay Lussac’s Law
P₁/T₁=P₂/T₂ where the volume is constant and the pressure and temp vary directly
Dalton’s Law of Partial Pressures
total pressure is equal to the sum of the partial pressures
Converting water -> Mercury
-divide the difference by 13.6
Ideal Gas Law
PV=nRT (where R can be .0821atm or 8.31kPa)
Ideal Gas Deviations
- least deviations occur at low pressures and high temps
- high deviations occur at high pressures and low temps
percent yield
actual yield/theoretical yield *100
capillary action
the attraction of the surface of a liquid to the surface of a solid
Le Chatlier’s Principle
- system will react to stress
- temp: ↑endo or ↓exo
- pressure: ↑less moles or ↓more moles
- conc: ↑away or ↓toward
Solids
- Crystalline
- Amorphous
- Polycrystaline
Water’s heat of vaporization
40.79 kJ/mol
Water’s heat of fusion
6.01 kJ/mol
anhydrides
- oxides that react with water to from acids and bases
- metal oxides form bases (known as basic anhydrides or basic oxides)
- nonmetallic oxides form acids (known as acidic anhydrides or acidic oxides)
General Rules of Solubility
- Solids: solubility usually ↑ when temp ↑; pressure has little effect
- Gasses: solubility usually ↓ when temp ↑; solubility varies in direct proportion to the pressure applied (Henry’s law)
Factors that affect Solubility
- ↑ surface area
- stirring
- heating
% Concentration
grams of solute/grams of solution *100 (10⁶ppm or 10⁹ppb)
Molarity
moles of solute/liters solution
Molality
moles of solute/kg solvent
Mole Fraction
moles of interest/total moles
dilution
M₁V₁=M₂V₂
heat of formation
- low: easy decomp
- high: extreme instability
heat of combustion
(combustion reactions)
Conditions for Completion
insoluble ppt formed
nonionizing substance formed
gaseous product given off
Hydrolysis
-salt and water react to form a base (opp of neutralization)
Standard State Condition
25C and 1atm
Hess’s Law of Heat Summation
when a reaction can be expressed as the algebraic sum of two or more other reactions; the heat of reaction is the algebraic sum of the heats of these reactions (based on 1st law of thermodynamics)
First Law of Thermodynamics
the total energy of the universe is constant and cannot be created or destroyed
Factors affecting Rate
- nature of the reactant/bonds
- surface area exposed
- concentrations
- temperature
- catalyst
Law of Mass Action
the rate of the chemical reaction is proportional to the product of the concentrations of the reactant (k is the specific rate constant that is only affected by temp)
Large Keq
equilibrium does not occur until the conc of the original reactants are small and those of the products are large
Small Keq
equilibrium occurs almost as once and and relatively little product is produced
Acid disassociation constant
Ka; incorporates the conc of water
Small Ka
conc of un-ionized molecule must be relatively large compared with ions conc
Large Ka
conc of ions are relatively high
pH
% dissociation
moles or liters that disassociate/original conc *100
Ksp
incorporates conc of solute
Second Law of Thermodynamics
entropy of the universe increases for any spontaneous process
Gibbs free-energy equation
∆G = ∆H -T∆S (where temp is in K) NOT C°
Characteristics of Common Acids
Water/aq solutions of acids conduct electricity
2) Acids will react with metals that are more active than hydrogen ions to liberate hydrogen
3) Acids have the abilit to change the color of indicators (such as Litmus)
4) Acids react with bases so that the properties of both are lost to form water and a salt
5) Acids react with carbonates to release carob dioxide
Arrhenius Theory
- Acids: a substance that yields hydrogen ions in an aq solution
- Bases: a substance that yields hydroxide ions in an aq solution
Characteristics of Common Bases
Bases are conductors of electricity in aq solutions
Bases cause a color change in indicators
Bases react with acids to neutralize each other and form a salt and water
Bases react with fats to form a class of compounds called soaps
Aq Solutions of bases feel slippery, and the stronger bases are very caustic to the skin
The Bronsted-Lowry Theory
- Acids: proton donors
- Bases: proton acceptors
Conjugate acids and bases
- acids give away a proton to become a conjugate base
- bases accept a proton to become a conjugate acid
- the stronger the base, the weaker the conjugate acid
- the stronger the acid. the weaker the conjugate base
Lewis Theory
- Acid: electron-pair acceptor
- Bases: electro-pair donor
Titration
M acid × V acid = M base × V base
5 Methods for Preparing Salts
Neutralization Single replacement Direct combo of elements Double replacements Reaction of a metallic oxide with a nonmetallic oxide
amphoteric substances
substances that donate protons in the presence of strong bases and accept protons in the presence of strong acids
Acid Rain
forms when oxygen, sulfur, and nitrogen combine in the atmosphere
Buffer solutions
resists changes in pH
Electrolyte
a substance that dissolves in water to form a solution that will conduct an electric current (if they don’t conduct…non electrolytes)
ionization
ions formed by breaking the covalent bonds
dissociation
ionic lattices come apart
Cations and Anions
- Cations: + (smaller than neutral atom)
- Anions: - (larger than neutral atom)
Tip: “OILRIG”
Oxidation Is Lost… Reduction Is Gained
-Dr. Brennan
Oxidation-Reduction
a substance that is oxidized during the reaction is separated from the substance that is reduced during the reaction; transfer of electrical energy NOT heat
“An Ox and a Red Cat”
anode is oxidation and reduction is cathode
electrochemical cell
system of electrodes and electrolytes in which either chemical reactions produce electrical energy or an electric current produced chemical change
voltaic/galvanic cell
redox reaction occurs naturally
allotropic
the existence of 2 or more different physical forms of a chemical element
Sulfuric Acid
acid salts; normal salts; ionization is more extensive; hydrogen sulfide is colorless other sulfides have colors
Halogen Family
colors at room temp; acceptors of electrons; Fluorine is most active (see pg 300 Barrons)
Metals
luster, conduct heat and electricity, malleable, ductile, silvery color most times, not soluble without chemical change
Carbon Dioxide
- in lab usually react carbon carbonate with hydrochloric acid
- test by passing it through limewater; cloudy if present
- stalagmites and stalactites form
- important for photosynthesis
Alkane Series
CnHn+₂ (hydrocarbon series) methane, ethane, propane, n-Butane…etc
alkyl halides
alkanes can be reacted with halogens so that hydrogens are replaced by a halogen atom
Alkene Series
-double covalent bond between 2 adjacent carbon atoms; CnH₂n
Alkyne Series
CnH₂n-₂ triple covalent bond between two adjacent carbons
Aromatics
unsaturated ring structures; CnH₂n-₆
Isomers
same formula, different structures
Alcohols (Methanol and Ethanol)
functional group; methanol is simplest alcohol; ethanol is best known and most used alcohol
Aldehydes
carbon double bonded to oxygen and single bonded to hydrogen and attached to an alkyl group
Organic acids
Carbon double bonded to oxygen and single bonded to hydroxide (Generally R-COOH)
Ketones
R-C-R and C is double bonded to Oxygen
Ethers
dehydrated with sulfuric acid R-O-R
Amines and Amino Acids
NH₂⁻ found in amide ions and the amino group; contain 1 or more amino groups; amide functional group is -N single bonded to 2 H’s
Esters
compared to inorganic salts; the functional group is R-C-O-R where C is double bonded to another Oxygen
Common Lab Tools
gravimetric balance with direct readings; pH meters; Spectrophotometer; Computer-assisted labs
Qualitative Tests of Some Metals
flame tests; hydrogen sulfide tests
Boiling point
increased by .51°C for every mole
