STATES OF MATTER Flashcards
Three Primary States of Matter
- Solid
- Liquid
- Gas
Mesophases
- Liquid crystalline state
- Supercritical fluids
- IM Forces is enough, but weaker than gasses
- has definite volume and shape
- dependent on the shape of the container
LIQUID
- greater kinetic energy than any molecules
- has no definite shape and volume
GAS
- impact and definite shape and size
- not dependent on the shape of the container
- molecules are locked in position
SOLID
Temperature – 0 degrees C or 273.13 K
Temperature
Addition of energy
heat
Gas molecules travel in random paths
THE GASEOUS STATE
Liquid to gas
evaporation
Solid to liquid
melting
force per unit area; recorded in atmospheres or in mm of mercury (mmHg)
Pressure
Gas to liquid
condensation
NH3 Critical temperature
132
Solid to gas
sublimation
Liquid to solid
freezing
A lot os space between the particles compared to the size of the particles themselves
Kinetic Molecular Theory
Gas to solid
deposition
Pressure is inversely proportional to volume
Boyle’s Law (PiV)
expressed in L or cubic centimeters
(1 cm3 = 1 mL)
Volume
The speed that the particles move increases with increasing temperature
Kinetic Molecular Theory
Ideal Gas Equation
PV = nRT
n = number of moles
R = Gas constant (0.0821 L. atm / mole K)
Pressure is directly proportional to Temperature
Gay-Lussac’s Law (PdT)
Gas constant
(0.0821 L. atm / mole K)
When there is a cooling or compression of gasses it will turn into liquid and vice versa.
Liquefaction of Gases
Volume is directly proportional to Temperature
Charle’s Law (VdT)
Collection of particles in constant motion
Kinetic Molecular Theory
the pressure required to liquify a gas at its critical temperature; highest vapor pressure that liquid can have;
Water’s CP = 218 atm
Critical Pressure
No attraction or repulsions between particles; collisions like billiard ball collisions
Kinetic Molecular Theory
CO2 Critical temperature
31.2
CO Critical temperature
-141
point where liquid does not exist
Critical point
NH3 Critical temperature
132
the temperature which a liquid can longer exist;
Water’s CT = 374 degrees C or 647 K
Critical Temperature
C2H6O (Ethanol) Critical temperature
216
C3H8 (Propane) Critical temperature
97
CH4 (Methane) Critical temperature
-82
H2O (Water) Critical temperature
37
SO2 (Sulfur dioxide) Critical temperature
157
CO Critical Pressure
35.9
C2H6O Critical Pressure
65
CH4 Critical Pressure
45.8
NH3 Critical Pressure
115
CO2 Critical Pressure
77
C3H8 Critical Pressure
42
SO2 Critical Pressure
77.8
H20 Critical Pressure
217.8
Depends on the cooling effect produced as gas expands using a Dewar or vacuum flask
Ideal gas expand rapidly and no heat enters system
Adiabatic expansion
Propellants
CFC, HFC, N, CO2
Highly compressed non-ideal gas expands into a region of low pressure
Leading to a drop in temperature resulting from energy used to bread the bonds between molecules
Necessary to pre cool the gas before expansion – gas does external work
Joule-Thompson Effect
A material that is liquid under the pressure conditions existing inside the container but that forms a gas under normal atmospheric condition
AEROSOLS
Gases can be liquefied under high pressures in a closed chamber as long as the chamber is maintained below the critical temperature.
When the pressure is reduced, the molecules expand and the liquid reverts to a gas
AEROSOLS
The temperature at which the vapor pressure of the liquid is equal to the external or atmospheric pressure.
BOILING POINT
When the rate of condensation is equal to the rates of vaporization at a definite temperature, the vapor becomes saturated and dynamic __________ is established.
equilibrium
- The presence of air above the liquid decreases the rate of evaporation (but EQ is not affected)
- As the temperature of liquid is elevated, more molecules approach the velocity necessary for escape and pass into the gaseous state = VP increases with increasing temperature
EQUILIBRIUM VAPOR PRESSURE
Expresses the relationship between the vapor pressure and the absolute temperature
Clausius-Clapeyron Equation:
Heat of Vaporization
All the heat absorbed is used to change the liquid to vapor, and the temperature does not rise until the liquid is completely vaporized
BOILING POINT
the heat absorbed by 1 mole of liquid when it passes into the vapor state.
Molar Heat of Vaporization
Water boils
760 mmHg =
100 degrees C (sea level)
BOILING POINT
Decreased by:
- Branching of chain
Water boils
700 mmHg =
97.7 degrees C
Water boils
17.5 mmHg =
20 degrees C
BOILING POINT
Increased with:
- Stronger intermolecular binding forces
- Increasing number of atoms
Mol. Wt. 88.1
Butyric acid
Mol. Wt. 111.1
Sodium butanoate
At higher elevations, the atmospheric pressure ________ and the boiling point is lowered
decreases
Mol. Wt. 88.1
Methyl propionate
Boiling point 163 degrees C
Butyric acid
Boiling point 80 degrees C
Methyl propionate
Boiling point >260 degrees C
Sodium butanoate
Strongest IMF Dipole - Dipole
Methyl propionate
Strongest IMF Ionic
Sodium butanoate
Strongest IMF Hydrogen Bonding
Butyric acid
IMF in order
Ionic > Hydrogen Bonding > Dipole - Dipole > Van der Waals dispersion forces (London Forces)
constructed from repeating units called “unit cells” – same size and contain the same number of molecules/ ions arranged in the same way.
Crystalline Solids
the quantities of heat absorbed when the liquid is vaporized and liberated when the vapors condensed to liquids.
Latent Heat of Vaporization
changes of the freezing/ melting point in pressure
Clapeyron equation
ability of the compound to exist in more than one crystal form with different cell parameters
Polymorphism
Its appearance is described by its overall shape or habit – where it affects:
- ability to inject a suspension containing a drug in a crystal form
- flow properties of the drug in the solid state
CRYSTALLINE SOLIDS
depend on the conditions of crystallization such as:
- solvents used
- temperature
- concentration & presence of impurities
Crystal habits
Drugs that exhibit polymorphism
- Tristearin (Triglyceride)
- Chloramphenicol palmitate
- Unstable liquid ritonavir
- Cortisone acetate
- Spiperone
- Tamoxifen citrate
- Carbamazepine
has the ff. pharmaceutical implications/ formulation problems:
- May be difficult to inject in suspension form or to formulate as tablets,
- Transformation during storage can cause changes in crystal size in suspension and eventual caking,
- Crystal growth in creams as a result of phase transformation can cause the cream become gritty.
- Changes in polymorphic forms of vehicles used to make suppositories could cause products with different/ unacceptable melting characteristics.
Polymorphism
When polymorphism occurs, the molecules arrange themselves in two/ more different ways in the crystal.
Polymorphism
susceptible to polymorphism
Sulfonamides & Barbiturates
crystallized by polar solvents (alcohols)
Beta polymorphs
a special case of polymorphism where substances exist in more than one crystalline form. (ex. carbon, sulfur)
Allotropic
when the change from one form to another is reversible.
Enantiotropic
crystallized by non polar solvents such (carbon tetrachloride and cyclohexane)
Alpha polymorphs
Types of Liquid Crystals
- Smectic
- Nematic
is a less stable (metastable) crystalline form of carbon. High pressure and temperature lead to the formation of a diamond from elemental carbon
Diamond
when the transition takes place in one direction only (ex. metastable to stable)
Monotropic
crystals that contain solvent of crystallization that arise from the entrapped solvent in the crystal.
Solvates
states that a system at equilibrium readjust so as to reduce the effect an external stress
Le Chatelier’s principle
CRYSTALLINE SOLIDS
Solvates
Hydrates
Anhydrates
when water is the solvent/ incorporated in the crystallization
Hydrates
crystals that have no water of crystallization
Anhydrates
“supercooled liquids” in which molecules are arranged in random manner as in the liquid state.
(ex. glass, polymers, gels,
beeswax, petrolatum)
Amorphous Solids
Amorphous solids differs from Crystalline solids in that they tend to flow when subjected to sufficient pressure over a period of time, and they do not have definite melting points.
Amorphous solids differs from Crystalline solids
the temperature at which a liquid passed in the solid state; also the Melting point of a pure crystalline compound
Freezing
exhibit similar properties in all directions
Isotropic
shows different characteristics in various directions along the crystals:
- Electrical conductance
- Refractive index
- Crystal growth
- Rate of solubility
Anisotropic
This is the temperature at which the pure liquid and solid exist in equilibrium at an external pressure of one atm
Freezing
heat absorbed when 1 g of solid melts; the heat liberated when it freezes.
Latent Heat of Fusion
considered as the heat required to increase the interatomic/ intermolecular distances in crystals (allowing melting to occur)
Heat of fusion
soap/ grease-like; molecules are mobile in two directions and can rotate about one axis
Smectic
A crystal that is bound together by weak forces has a low heat of fusion and a low melting point; strong forces – both high
Melting point and Intermolecular Forces
thread-like; molecules rotate only about one axis but are mobile in three dimensions
Nematic
- Mobile, have the flow properties of liquids
- Birefringent, the light passing through a material is divided into different velocities and refractive indices
Liquid Crystals
formed from the gaseous state where the gas is held under a combination of temperatures and pressures that exceed the critical point of a substance
mesophase
Applications of Superficial Fluid:
- Extraction
- Crystallization
- Preparation of formulation
- Decaffeination of coffee
Formulated by J. Williard Gibbs; a relationship for determining the least number of intensive variable that can be changed without changing the equilibrium state of the system.
PHASE RULE
a homogenous, physically distinct portion of a system separated from otherportions of the system by bounding surfaces
Phase
smallest number of constituents by which the composition of each phase in the system at equilibrium can be expressed in the form of a chemical formula/ equation
Number of components
CaCO3 = _______ + ________
combination of any 2 of the chemical species present
CaCO3 = Calcium Oxide + Carbon dioxide
maximum temperature at which two-phase region exists
Ex. Water and Phenol
Critical Solution
solid-liquid mixtures in which two components are completely miscible in the liquid state and completely immiscible as solids
Ex. salol-thymol, salol-camphor, & acetaminophen-propyphenazone
Eutectic Mixtures
the point at which the liquid and solid phases have the same composition/ eutectic composition
Eutectic Point
composition of two or more compounds that exhibit a melting temperature lower than that of any other mixture of the compounds
Eutectic Composition
On a phase diagram, the intersection of the eutectic temperature and the eutectic composition gives the ________
eutectic point
Two-component systems containing Liquid Phases
Systems containing one component
Condensed systems
