It is largely governed by electron.

It is the cohesion or the attraction of like molecules and adhesion or attraction of unlike molecules

Van der Waals forces relate to nonionic interactions between molecules.

It involves charge-ion interaction.

Found in covalent bonds

True about Van der waals:

I. It has a weak forces

I. Dispersion of charge across a molecule called dipole

III. It has a temporary dipole

IV. It is to polarize the charge

The permanent dipole interact with one another. The strength of bonding is much weaker

Non polar molecules can induced polarity in one another

Permanent dipole are capable of inducing electric dipole in non polar molecules, which are easily polarizable

(3-4) X 10 ^-8 cm (3-4)

A permanent dipole to polarized charge in a neighboring molecule

Which of the following are true:

I. Keesom forces also known as induce -dipole

II. Debye forces also known as dipole-induced dipole

III. London forces also known as induced-dipole-induced-dipole

Two neighbhoring neutral molecules. Example is aliphatic hydrocrabons

Large groups of molecules may be associated through weak interactions

Are considerably stronger than many of the forces described in this section and can even be stronger than covalent bond when ionic bond is formed

Strongest bonding

On one compound will interact with an ionic or another compound given rise to an intermolecular association

Strongly electronegative atom

I. Electrovaleny bond between two counter ions is the strongest bonding interaction and can persist over longest distance.

II. Weaker ion-ion interactions in particular salt formations, exist and influence pharmaceutical systems

When sufficient energy is supplied, the atom or molecules passed into

Hydrogen bonds form an electrostatistic type of union known hydrogen bridge.

It was discovered by Latimer and Rodebush in 1920.

Reverse process of sublimation

Fourth phase which lies between the liquid and crystalline state is called

Pressure a force per unit area expressed in

Pressure is also recorded in atmosphere or in

Solids with high vapor pressure such as __________ and _______ can pass directly from solid to gaseous state without melting at room temperature

Zero degrees on centigrade is equal to

temperature involved in the gas equation is given according to the

Volumes is also expressed as

It is also considered as a mesophase

Manufacturing of heat-sensitive drugs

Drug suspended in water is frozen and then dried by what process

I. Freeze drying are most common commercial approach to making a sterilized powder

II. Injectable formulation where a suspended drug might undergo rapid degradation , thus a dried powder is preferred.

Gas law formulated by

Refer to an ideal situation where NO intermolecular interaction exist. And collision are perfectly ELASTIC, and no energy is exchanged upon collision

Process of Freeze drying in order:

I. Vials are loaded onto trays and place in lyophilizer

II. Drug is formulated in a sterile buffer and place in a vial

III. Slotted stopper is partially inserted into the vial.

IV. Upon completion of the primary freeze, vacuum is applied and the water sublimes into vapor and is removed from system

V. The stoppers are then condensed into the vials to seal them and the powders are left remaining in a vacuum sealed container with no air exchange.

VI. The temperature is raised to add more energy to the system, and a secondary freeze drying cycle is performed under vacuum to pull off more on the tightly bound water.

The temperature above which is a liquid can no longer exist, is known as

Approximate molecular weight can be identified using

The pressure required to liquefy a gas at critical temperature is the

Liquefaction of gases statements that are true;

I. Gasses is cooled

II. It loses some of its potential energy in the form of heat

III. Velocity of the molecules decreases if pressure is applied to a gas

IV. Molecules are brought within the sphere of the van der waals interaction forces and pass into the liquid state

V. Temperature is elevated sufficiently

Allow an ideal gas to expand so rapidly that no heat enters the systems, such as expansion termed an

Critical temperature is

Critical Pressure is

A cooling effect is also observed when a highly compressed ________ expands into a region of low pressure

Effectively insulates the contents of the flask from the external Environment

Cooling effects is known as the

Gases can be liquefied under high pressures in a closed chambers a long as the chamber is maintained below the critical temperature

In aerosol, when the pressure is reduced, the molecules expand and the liquid revert to a solid

Examples of traditionally been utilized as propellants because of physichochemical properties

Obviously to liquefy a gas is to subject it to intense cold by the use of

If the drug is volatile, it forms a fine spray as it leaves the valve orifice, at the same time the liquid propellant vaporizes off

A drug is dissolved in a ____ a material that is liquid under the pressure conditioned existing inside the container but the forms a gas under normal atmospheric conditions.

It is used a cool sufficiently on expansion so that when sprayed on the skin, it freezes the tissue and produces local anesthesia

Pulmonary and nasal routes of administration enable higher rate passage into systemic circulation than does oral administration

In vapor pressure of liquids, when a liquid is placed in an evacuated container at a constant temperature, the molecules with the highest energies break away from the surface of the liquid and pass into the gaseous state and some of the molecules subsequently return to the liquid state or condensation

When rate of condensation equals the rate of evaporazation at a definite temperature the vapor becomes saturated and a dynamic equilibrium is established

This can be sprayed onto braded skin with a minimum of discomfort to the patient

Proteins, DNA, oligopeptides and nucleotides all demonstrate oral poor oral bioavailability due to the harsh environment of the gastro intestinal tract and their relatively large size and rapid metabolism

Presence of gas, such as air above the liquid increase the rate of vaporization

The pressure of saturated vapor above the liquid is known as the equilibrium vapor pressure

The change in boiling point with pressure can be computed using

These quantities of heat is known as ______ are taken up when the liquid vaporize and are liberated when the vapors condense to liquids

Vapor pressure increases with rising temperature

For benzene, the heat of vaporization is 91.4 cal/g at the normal boiling point of 80. 2C

It is the relationship between the vapor pressure and the absolute temperature of a liquid is expressed by the

Structural unit of crystalline solids such as

Heat of vaporization at 100 c is 539 cal/g or about 9720 cal/mole

Have a definite shapes and orderly arrangement of units

Crystalline solid show definite melting point , passing rather sharply from the solid to the liquid state

The boiling points of normal hydrocarbons, simple alcohols and carboxylic acids increase with molecular weight because attractive van der waals foces become greater with increasing number of atoms

It is a morphology of a crystalline form.

It is defines as having the same structure but different outward appearance

Columbic forces and hydrogen bonding which account for the weak bonding and for the low melting points of these crystals.

I.The level of saturation from which the material is crystallized generally the higher concentration above the solubility , the more chance metastable form is seen.

II. Common example of polymorphism is the contrast between diamond and a graphite

I.Metallic crystal are composed of positively charged ions in the field of freely moving electrons, sometimes called electron gas.

II. Metals are good conductors of electricity because of the free movement of the electrons in the lattice

Some elemental substances , such as carbon and sulfur may exist in more than one crystalline form are_____. . It is a special case of polymorphism

Solvates are sometimes called

Four Polymorphic forms

I. Residual solvents can be trapped in the crystalline latices.

II. It creates cocrystal

When the change from one form to another is reversible it is said to be

When the transmission takes place in one direction only for example form a metastable to a stable form the change is said to be

Considered as supercooled liquids

Amorphous solid body shows an elastic properties is known as

Substance such as glass, pitch and many synthetic plastics are amorphous solids

_____ is important in polymorphism because it helps characterize the systems and determine the more stable form at temperature of interest.

I. Cubic crystals are usually isotrophic.

II. Crystal other than cubic are anisostrophic

The heat energy absorbed when 1g of solid melts or the heat liberated when it freezes is known an Latent heat of fusion

Heat of fusion may be considered as the heat required to increase the interatomic or intermolecular distances in crystal allowing melting to oocur

temperature of the equilibrium mixture at the external pressure of 1 atm this is sometimes known as normal freezing or melting point

The temperature at which a liquid passes into the solid state is known as

Fourth phase of matter

Supercriticals fluids were first described more than 100 years ago and can be formed by many different normal gasses such as carbon dioxide.

Molecules rotate again only about one axis but are mobile in three dimension

Smectic mesophase usually forms in ternary ( or more complex) mixtures containing a surfactant, water and weaj=kly amphophilic or nonpolar additives

Molecules are mobile into two directions and can rotate one axis

Advantages of Supercritical fluids over traditional methodologies

Common uses of supercritical fluids

Smetic (soaplike or greaselike)

Nematic ( Threadlike)

Molecules that form mesophase