States Of Matter Flashcards
MmHg
Unit of measure for pressure based on barometer readings
Pressure
The distribution of a force across a designated area
P=Fn/A
Torr
Unit of pressure equal to 1mmHg
Pascal (Pa)
Unit of pressure
Pa= 1 N/m^2
atm
Unit of pressure measure based on sea level Generally accepted =101,325 Pa =29.92 mmHg =14.7 psi
Manometer
Laboratory equipment used to measure pressure
Simple gas laws
1) boyles law
2) charles law
3) avogadros law
Boyles law
V1P1=V2P2
Charles’ law
V1/T1=V2/T2
Avagodro’s law
V1/n1=V2/n2
Ideal gas law
PV=nR*T
R=0.08206
atm, L, mol, K
Ideal Gas Constant
R=0.08206
Molar Volume
Volume occupied by one mole of a substance
Standard temperature
0 C = 273 K
Standard pressure
1 atm
Gas density
Density = (molar mass)/(molar volue)
Partial pressure
Presure exerted by an individual gas in a mixture
Pn=nn (RT/V)
Daltons law
The sum of all partial pressures is equal to the total pressure
Kinetic molecular theory
Gas is represented by a series of tiny particles
1) the size of a particle is negligably small
2) the kinetic energy of each particle is proportional to the temperature in Kelvins
3) The collision of one particle with another results in an exchange of energy
Work on the Kinetic molecular theory with the gas law
226
Avagadros number
NA= 6.022x10^-23
Mole
Avagodros number of atoms (or molecules) of a given substance
Kinetic energy of a given particle
KE=1/2 (m*v^2)
Lighter particles carry more kinetic energy
Average kinetic energy
KE=(3/2)RT
Mean free path
The average distance a particle travels between collisions
Diffusion
The process by which gas molecules spread out in response to a concentration gredient
Effusion
Process by which gas escapes from a container into a vacuum through a small hole
Graham’s law of effusion
Describes the relationship between effusion rates
RateA/RateB = sqrt(molar massB/molar massA)
Gas law correction for volume
V=nRT/P+ nb
b is a constant represented by individual gasses
Gas law correction for pressure
P=nRT/V- a(n/V)^2
a is a constant represented by individual gasses
Vanderwals equation
[P+a(n/V)^2]x[V-nb]=nRT
Product of Corrected gas volume and corrected Volume equals the rest of the ideal gas law
Pressure-Volume relationship to atom count
PV=NkT
N=number of atoms
k=boltzman constant=1.38x10^-23
Boltzman constant
1.38x10^-23
Liquid
Definite volume
Assumes the shape of a container
Solid
Definite Volume Definite Shape High density Particles packed closely together Low kinetic energy
Gas
No definite volume, No definite shape Low density Maximum space between particles High kinetic energy
Melting
Physical change from solid to liquid
Evaporation
Physical change from liquid to gas
Sublimation
Physical change from solid directly to gas
Condensation
Physical change from gas to liquid
Freezing
Physical change from liquid to solid
Deposition
Physical change from gas to solid
Intermolecular forces
Forces that hold condensed (non-gaseous) states together
Dispersion force
Result of fluctuations in the electron distribution within molecules and atoms
Dipole-dipole forces
In polar molecules, forces that keep maintain the molecular geometry of a molecule
Miscilibility
The ability to mix without separating into separate states
Ion-dipole forces
Result of a polar compound mixing with an ionic compound
Surface tension
Energy required to increase the area of the liquid by a given unit
Viscocity
The resistance of a liquid to flow
Capillary action
The ability of a liquid o flow against gravity up a narrow tube
Volatile
A liquid’s ability to vaporize easily
Nonvolatile
Refers to liquids that do not vaporize easily
Phase Diagram
Pressure/temperature chart in which the phases are mapped out with the fusion curve, sublimation curve, and vaporization curve with the triple point where they all meet
Critical point
The point of maximum temperature and pressure at which substances become a superficial liquid, neither liquid nor gas
Sublimation curve
The line on the phase diagram lowest on the pressure/temperature chart
Higher pressure yeilds solid
Higher temperature yeilds gas
Fusion curve
The line that separates liquids from solids on the phase diagram
Runs up from the ‘triple point’
High temperature yields liquid
Low temperature yields a solid
Vaporization curve
The line on the phase diagram that seperates liquid from gas
Splits right from the triple point
High pressure yields liquid
High temperature yields gas
Triple point
The point at which the temperature pressure ratio is at a delacate balance, where the smallest change in either variable could change the phase of the substance
Crystalline structure
A solid in which atoms molecules or ions are arranged in patterns with long range repeating order
Solution
A homogeneous mixture of two substances
Solvent
Majority component in a solution
Solute
Minority component of a solution
Aqueous Solutions
A solution in which water is the solvent
Solubilty
The amount of a substance that will dissolve in a given amount of solvent
Natures mixing tendency
The resulting solution will be the lowest energy level possible
Entropy
A measure of energy dispersal within a system
Properties of the ideal gas
Molar Volume 22.41L at STP
No adjustment for VP=nRT
(V/nRT)=1
Miscible substances
Substances that are soluble in one another
Exothermic
Heat is given off, feels hot
Endothermic
Absorbs thermal energy, feels cold
Solution prosses
1) Solute is broken into constituent particles (endothermic)
2) The solvent particles separate to make room for the solute particles (endothermic)
3) Solute are dispersed throughout solvent (exothermic)
Enthalpy of solution
The sum of the enthalpies for each step in the solution process
ΔH=Δh-solute seperation+Δh-solvent seperation+Δh-mixture
Heat of hydration
The sum of the heat of solvent separation (endothermic) and and the heat of the mixture (exothermic)
Dynamic equilibrium
The point at which the rates of dissolution and recrystaization become equal
Saturated solution
Solution in which the amount of dissolvable solute has already been reached,
If any more solute is added, it will not dissolve
Nonsaturated solution
A solution that could still dissolve more solute
Supersaturated solution
Solution containing more solute than could be disolved in that solvent
Recrystalization
A purification technique by which a solid is added to water to create a saturated solution at a high temperature, as the solution cools, it becomes over saturated and produces crystals of the dissolved solid
Factors in solubility
1) Volume
2) Temperature
3) Pressure
Henrys law
Solubility of a gas (units of M) is equal to the product of henrys law constant (k sub-h, individual to each gas) and the partial pressure of that particular gas
S=k*P
Dilute solution
Solution containing some small quality of solute relative to the amount of solvent
Concentrated Solution
A solution containing a large quantity of solute, relative to the solvent
Molarity (M)
(Moles of solute)/(volume of the solution in L)
Molality (m)
(Moles of solute)/(mass of solvent in Kg)
Percent by mass
Way of representing the saturation of a solution
(Solute mass)/(solution mass)x100%
Parts per million (ppm)
(Mass solute/mass solution)x10^6
Parts per billion (ppb)
(Mass solute/mass solution)x10^9
Parts by volume
(Volume solute)/(volume solution)x(multiplication factor)
Usage of parts by mass or volume
Find the mass or volume of the solution given the solute specifications (vice versa)
Mole fraction
(Moles Solute)/(moles of solute and solvent added) x100%
Colligative property
Any property that depends on the number of particles dissolved in a solution
Raoult’s law
The vapor pressure of the entire solution is equal to the product of the mole fraction and the vapor pressure of the pure solvent
See page 571 for practice
Ideal solution
When both the solute and solvent are volitile, contributing to the vapor pressure of the overall solution
Freezing point depression
lowering the freezing point of a solution,
Colligative property
ΔTf=m*Kf
m-molality
Kf freezing point depression constant for the solvent
Boiling point elevation
Ease of Raising the boiling point of a solution,
Colligative property
Osmosis
The flow of a solvent from a solution of lower solute concentration
Semipermeable membrane
A material that effectively filters some substances but not others
Osmotic pressure
Equal to molarity times the gas constant times solution temperature
MRT
Van’t Hoff factor
i=(moles of particles in solution)/(moles of formula units dissolved)
Colloids
A substance in which fine particles (between 1nm 1000nm in size) are evenly dispersed,
ie Milk
Micelles
Non-polar hydrocarbon trails crowd into the center of a shape to maximize their interactions with one another
Tyndall effect
The scattering of light by colloidal dispersion
Moles present
(mass present)/(substance molar-mass)
Aqueous solution
A solution in which water acts as the solvent
Dilution equation
M1V1=M2V2
Electrolytes
Solutes that dissolve into ions that conduct electricity
Strong electrolytes
Electrolytes that dissolve completely in water
Non-electrolytes
Solutes whose ions do not conduct electricity
Strong acid
An acid that completely ionizes in water
Weak acids
An acid that does not completely ionize in water
Weak Electrolytes
Electrolytes that that do not dissolve completely in water
Solubility rules
1) Group1 and Amonia cations
2) Nitrates and acetates
3) Chlorides, Bromides, Iodines (Ag1, Hg2, Pb2)
4) Sulfate (Sr2, Ba2, Pb2, Ag1, Ca2)
5) But not hydroxide or sulfide (Unless rule 1 applies, Ca2, Sr2, or Ba2)
6) But not carbonates or phosphates (unless rule 1)
Precipitation reactions
When a solid (precipitate) is formed by the mixing of two solutions
Precipitate
Solid formed by mixing two solutions
Acid solutions
Acids release H+ ions in the presence of water
Basic Solutions
Bases release OH- in the presence of water
Hydronium ions
H+(aq) ions released by an acid in water
Titration
Substance in a solution of a known concentration is reacted with another substance in a solution of unknown concentration
Equivilence point
In an acid base reaction, the Point at which moles of OH- equal moles of H+
Indicator
A dye used that changes color based on acidic exposure, used to indicate equivalence point of a solution
Structural Isomers
Atoms are connected to one another in a variety of ways
Stereoisomers
Atoms are connected in the same way, with a variety of specially arrangements about the metal atom
Coordination isomers
Occurance of a coordinated ligand exchanging places with an uncoordinated counterion
Linkage isomers
Stereoisomers that have ligands that coordinate to the metal in different geometric orientations.
Geometric isomers
A type of stereoisomerism that results from ligands bonding to metal in a variety of spacial arrangements
Hydroscopy
The ability of a substance to pull moisture from the surrounding environment
Crystallgraphic deffect
Interruptions in the regular pattern of fixed repeating order solids (crystals)
Microcrystaline
A solid that contains crystals visible only through microscopic examination
Cubic crystal system
A crystal system in which the unit cell is in the shape of a cube
Toms are arranged in cubic order
Crystal family (lattice system)
Several classes of crystaline structures that have similar symmetries
Is it polar (from the chemical formula)
Determine the molecular geometry
Is it has lone pair electrons, it is polar
Cone shaped bond in complex molecules
Look it up
Dashed bond in complex molecules
Look it up
Complex molecular orbit calculations
Practice
Disiccant
Hygroscopic material that induces dryness in surroundings
Brauner-Emmet-Teller (BET) theory
Solids are capable of absorbing gas particles at their surface
Langmuer Equation
Reated the quantity of gas molecules absorbed by the surface of a solid to the gas pressure
Calculating Ph value from hydrogen ion activity
Ph=log(1/[H+])
Where h+ refers to the hydrogen ion activity of a solution
Supercritical drying
Transitioning a material from a liquid to a gas by raising the temperature and pressure beyond the supercritical point, and then lowing the pressure until the substance become a gas
Surface energy
The quantitive measurement of the bonds disrupted by the formation of a surface
Excimer
‘Excited dimer’
A short-lived molecule, formed from two species, with a filled vallance shell (noble gas)