Ex. of Solute

(a)  

are defined as the component of a solution present in the greater or greatest amount

(a)  

Ex. of Solvent

(a)  

is a homogeneous mixture, meaning it is a combination of substances so thoroughly mixed as to appear to be one substance.

(a)  

is a scalar quantity and defined as the ratio of mass per unit volume.

(a)  

where ρ is the ______ m is the _____ v is the _______

(a)  

g/cm^3 and g/mL are?

(a)  

- is also known as "relative density". - is the ratio of the density of the substance to that of water (1 g/mL )

(a)  

Expression of concentrations

(a)  

- In all the techniques of quantitative analysis, the use of solutions requires some basis for the expression of solution concentration.

(a)  

- Number of moles of solute (substance) dissolved in one liter (1000mL) of solution.- 1 gm in 1000mL = 1 mol- is indicated by M (mol/L)

(a)  

- Number of gram equivalent of solute (substance) dissolved in one liter (1000mL) of solution- is indicated by N (eq/L)

(a)  

- a measure of the number of moles of solute in a solution corresponding to 1 kg or 1000 g of solvent.- is indicated by m (mol/kg)

(a)  

- the ratio of the number of moles of one component of a solution or other mixture to the total number of moles representing all of the components

(a)  

- expressed as a decimal, to obtain the number of grams of solute or constituent in the solution or liquid preparation.- sometimes the concentration is expressed in terms of per cent (parts per hundred) also.

(a)  

When molecules interact with each other, they do so by the forces of both attraction and repulsion. Forces of attraction are essential for molecules to come together

(a)  

TWO TYPES OF ATTRACTIVE FORCES

(a)  

when like molecules are attracted to each other

(a)  

When different molecules are attracted to one another

(a)  

Attractive forces (FA) are (a)   to the distanceseparating the molecules (r)

The inverse relationship between the forces of attraction and the distance has been derived from the phenomena first described by _______and is known as the __________.

(a)  

attractive forces can be represented by means of a potential energy function. As the forces of attraction between the molecules increase, the potential energy becomes increasingly negative

(a)  

Repulsive forces (FR) are (a)   with the reciprocal of the distance separating the molecules (r)

By convention, the force F acting between twomolecules that are close together is _____ when it is _____ and _____when it is _______.

(a)  

The distance between the molecules at which the attractive and repulsive forces just balance each other is the

(a)  

INTERMOLECULAR FORCES

(a)  

forces relate to nonionic interactions between molecules, yet they involve charge -charge interactions. They are weak forces compared with the covalent bond, which is generally 50 to 100 kcal/mole, and the ionic bond, which rangesfrom 100 to 1000 kcal/mole.

(a)  

TYPES OF VAN DER WAALS FORCES:

(a)  

occur when polar molecules possessing permanent dipoles, having both a partial positively charged end and a partial negatively charged end, interact. The energy of this attraction ranges from 1 to 7 kcal/mole.

(a)  

A polar molecule can produce a temporary electric dipole in nonpolar molecules that are easily polarizable. The forces of attraction are weaker, being about half those of dipole-dipole forces. The energy of this type of attractive force is 1 to 3 kcal/mole.

(a)  

These are forces that originate from molecular internal vibrations in nonpolar molecules to produce attraction that arises because of synchronized fluctuating dipoles inneighboring atoms.

(a)  

Molecules that are polar are attracted to either positive or negative charges. The energy of attraction is about 1 to 7 kcal/mole.

(a)  

- Negative ion attracts the partially positive end of a neutral polar molecule.- Positive ion attracts the partially negative end of a neutral polar molecule.

(a)  

Pharmaceutical salts will have ion dipole forces holding the drug molecule and the counterion together. In the case of a carboxylic acid, the hydrogen atom will be removed resulting in a negative charge. The positive ion that bonds to form the salt can be an inorganic species, such as sodium or potassium, or an organic species, such as arginine or choline.

(a)  

The forces of attraction are induced by the close proximity of a charged ion to the nonpolar molecule

(a)  

These attractive forces account for the solubility ofionic crystalline substances in water, where a cationattracts the large negative oxygen of water and ananion attracts the hydrogen atoms.

(a)  

A specific type of electrostatic attraction between molecules and parts of molecules is the hydrogen bond. This bond can be intermolecular or intramolecular.

(a)  

accounts for the unusual properties of water relative to hydrogen compounds of other group 6A elements

(a)  

important for protein α-helix and β-sheet structures; conformation of proteins; physical properties of alcohols compared to alkanes; carboxylic acids compared to esters, aldehydes, and ketones; and sugars. In a compound, the formation of a hydrogen bond in an aqueous solution with water or in the structure of the compound modifies both the physical properties and to some extent the chemical properties

(a)  

in maintaining protein structure are those between the peptide backbone -NH groups and the backbone carbonyl groups

(a)  

are forces of attractionbetween nonpolar atoms and molecules in water.They cause the nonpolar species to be driven togetherand are critical for the structure and stabilization of many molecules.

(a)  

forces of attraction within the molecule

(a)  

TYPES OF INTRAMOLECULAR FORCES

(a)  

- Transfer of electrons betweena non metal & a metal- Observed in formation of salts , example NaCl

(a)  

- Sharing of electrons between two non metals- Observed in organic compounds , example CH4

(a)  

- The attraction between +ions and the sea of free moving electrons is the metallic bond that holds atoms together- Usually the strongest type of chemical bond, example Au Ag Co

(a)  

STATES OF MATTER

(a)  

The state of matter in which the atoms or molecules are locked into place by either chemical bonds or forces between molecules called

(a)  

particles are arranged and packed closely and are relatively stable

(a)  

CHARACTERISTICS OF SOLID

(a)  

Solids are generally divided into three broad classes;

(a)  

- Solids have a very high degree of order in a periodic atomic arrangement.- Practically all metals and many other minerals,such as common table salt ( sodium chloride ), belong to this class.

(a)  

- Solids are those in which atoms and molecules are not organized in a definite lattice patterns. They include glasses, Plastics and gels.

(a)  

- Solids display novel symmetries in which the atoms are arranged in quasiperiodic fashion i.e in patterns that do not repeat at regular intervals.

(a)  

an example of a cooled liquid which has become solid.

(a)  

- The only state with a definite volume but no fixed shape.- are denser than gases and possessless kinetic energy than do gases.- Can change state

(a)  

- almost incompressible- have their boiling points above room temperature, under normal conditions- have fixed volume but no fixed shape- flow from higher to lower level

(a)  

PHYSICAL PROPERTIES OF LIQUID

(a)  

- Equilibrium (a)   does not depend on the volume or weight of the liquid or on the atmospheric pressure or the presence of other vapors in the air. it does depend on the temperature.- The temperature involved in the gas equations is given according to the absolute or Kelvin scale.

Vapor pressure is recorded in

(a)  

Relationship between temperature & vapor pressure

(a)  

A therapeutic compound where vapor pressure at room temperature is an important consideration

(a)  

- are force per unit length; generally, the units used are dynes · cm-1- Molecules in the bulk of the liquid are attracted to each other by intermolecular forces. Molecules on the surface are attracted inward by the bulk and outward into the phase it is in contact with, thus creating an unequal distribution of attractive and potentially repulsive forces that is based on the chemical nature of the phases.

(a)  

The high surface tension of water can inhibit it from readily dissolving powders with hydrophobic crystal surfaces

(a)  

there are means to reduce the surface tension that tend to lower the energy of attraction of the molecules in the liquid which is the (a)  

EXAMPLES of liquid

(a)  

GAS STATE OF MATTER Characteristics

(a)  

- travel in ramdom paths and collide not only with one another but also in the wall of a container in which they occupies.- They show high diffusibility, thermal expansionand high compressibility have empty spacesbetween molecules They always form ahomogenous mixture. (e.g., hydrogen, helium,oxygen)

(a)  

CHARACTERISTICS of Gas

(a)  

- A force per unit area, expressed in dynes/cm²- Also recorded in atmosphere or in millimeters of mercury because of the used of barometer in pressure measurement.- Gaseous pressure is measure by a manometer while the atmospheric pressure is measure by a barometer.- Usually expressed in meters or in cubic centimeters ( 1cm³= 1 ml)- The temperature involved in the gas equations is given according to the absolute or Kelvin scale

(a)  

- V1/T1=V2/T2- at constant P, as the volume increases the temperature also increases- "the volume occupied by a fixed amount of gas is directly proportional to its absolute temperature, if the pressure remains constant."

(a)  

- P1V1=P2V2- At constant T, id the pressure increases then volume decreases- "the pressure exerted by a gas is inversely proportional to the volume occupied by it at a constant mass and temperature."

(a)  

- P1/T1=P2/T2- At constant V, as pressure increases the temperature also increases- "the pressure of the gas is directly proportional to the temperature for a given gas, at a constant volume"

(a)  

- V1/n1=V2/n2- V/n=constant- When the amount of gas increases, the volume of the gas also increases- "under the same conditions of temperature and pressure, equal volumes of different gases contain an equal number of molecules"

(a)  

PV=nRT- Obey gas laws under all conditions of temperature and pressure- No gas is ideal in reality- Force of attraction is absent beetwen this molecules- Volume of molecules is negligible as compared to he total volume of the gas- "the product of the pressure and the volume of one gram molecule of an ideal gas is equal to the product of the absolute temperature of the gas and the universal gas constant."

(a)  

Real life ex. of Gay-Lussac's Law

(a)  

(a)   was developed by Henry Eyring in 1935 at the University of Manchester and is a very important factor in the chemical reaction that determines the rates of chemical reaction taking place in an elementary reaction. This theory functions on quasi-equilibrium, which is a chemical equilibrium that is established between the reactants when the reaction started and the complexes that had attained an activated transition state.

Transition State Theory was developed by _________ in ______ at the ________ and is a very important factor in the chemical reaction that determines the rates of chemical reaction taking place in an elementary reaction.

(a)  

a chemical reaction is basically a configuration attended by reactants during complex formation along with the reaction coordinates where maximum potential energy is attained.

(a)  

Transition-state theory also called as

(a)  

its state is referred to as the transition state.

(a)  

it represents the minimum energy that a reacting or flowing system must acquire for the transformation to take place. In transition-state theory, the activated complex is considered to have been formed in a state of equilibrium with the atoms or molecules in the initial state, and therefore its statistical and thermodynamic properties can be specified.

(a)  

- is when a substance changes from a solid, liquid, or gas state to a different state. Every element and substance can transition from one phase to another at a specific combination of temperature and pressure.- are the physical processes of transition between a state of a medium, identified by some parameters, and another one, with different values of the parameters. Commonly the term is used to refer to changes among the basic states of matter: solid, liquid, and gas, as well as plasma in rare cases.

(a)  

Each substance has three phases it can change into; solid, liquid, or gas. Every substance is in one of these three phases at certain temperatures. The temperature and pressure at which the substance will change is very dependent on the intermolecular forces that are acting on the molecules and atoms of the substance.

(a)  

These processes are reversible and each transfers between phases differently:

(a)  

The transition from the solid to the liquid phase

(a)  

The transition from the liquid phase to the solid phase

(a)  

The transition from the liquid phase to the gas phase

(a)  

The transition from the gas phase to the liquid phase

(a)  

The transition from the solid phase to the gas phase

(a)  

The transition from the gas phase to the solid phase.

(a)  

There are two variables to consider when looking at phase transition, pressure (P) and temperature (T). For the gas state, The relationship between temperature and pressure is defined by the equations below:

(a)  

also known as the general gas equation, is an equation of the state of a hypothetical ideal gas.PV=nRT(1)van der Waals Equation of State:(P+a∗n2V2)(V−nb)=nRT(2)Where V is volume, R is the gas constant, and n is the number of moles of gas.

(a)  

can change the phase of a substance. This type of phase change is called an isobaric process because the pressure of the system stays at a constant level

(a)  

is the temperature that a solid will become a liquid. At different pressures, different temperatures are required to melt a substance. Each pure element on the periodic table has a normal melting point, the temperature that the element will become liquid when the pressure is 1 atmosphere.

(a)  

is the temperature that a liquid will evaporate into a gas. The boiling point will change based on the temperature and pressure. Just like the melting point, each pure element has a normal boiling point at 1 atmosphere.

(a)  

can also be used to change the phase of the substance.

(a)  

F=C-P+2The phase was proposed by J. Willard Gibbs in 1876. It relates number of independent variables or degree of freedom (F), number of phases that can coexist (P) and number of components making up the phases (C) in a system at equilibrium. The least number of independent variables or degree of freedom (i.e. temperature, pressure, concentration, density) can be correlated with number of phases and components for any system at equilibrium using the following equation

(a)  

To reduce complexity in the phase diagram, we consider pressure 1 atm and thus we neglect the existence of vapor phase.Equation is as follows:F=C-P+1

(a)  

- Three phase (P = 3) solid, liquid and vapor coexist, so degree of freedom is- This implies that in a system containing single component, this three-phase mixture can only exist at a single temperature and pressure, which is known as (a)  

This implies that in a single phase condition, two variables temperature and pressure can be controlled to any selected pair of values. However, if the single component undergoes a separation into two phases (P = 2), F changes from 2 to 1. However, it is not possible to independently control temperature and pressure because change in either of one causes change in other one.

(a)  

Applying phase rule for the water and phenol partially miscible system for the region outside curve (P = 1)Considering the system as condensed system, the pressure can be neglected and value of F equalizes 2. Thus, the system is declined by the temperature and concentration of one component.

(a)  

- The two-components are immiscible as solids but are miscible as liquids.- Curve AE denotes the freezing of salol and curve BE denotes the freezing of thymol.- Point A denotes melting point of salol and point B denotes melting point of thymol.- Region above AEB—existence of single phase system.- Point E is called as eutectic point. At this point, solid salol and thymol and liquid phases of salol and thymol coexist.

(a)  

Applying phase rule for a three-component system, the degree of freedom are as follows:

(a)  

This accounts for temperature, pressure and concentration of anytwo components.The phase diagrams for three-component systems are representedby using a triangle whose vertices represents various componentspresent

(a)  

- a visual representation of how a substance changes phases.- a phase change occurs. In addition, two states of the substance coexist in equilibrium on the lines or curves.

(a)  

is the transition from one state of matter to another. There are three states of matter: liquid, solid, and gas.

(a)  

A state of matter that consists of loose, free moving particles which form the shape set by the boundaries of the container in which the liquid is in.

(a)  

A state of matter with tightly packed particles which do not change the shape or volume of the container that it is in.

(a)  

A state of matter where particles are spread out with no definite shape or volume. The particles of a gas will take the shape and fill the volume of the container that it is placed in.

(a)  

the point on a phase diagram at which the three states of matter: gas, liquid, and solid coexist.

(a)  

the point on a phase diagram at which the substance is indistinguishable between liquid and gaseous states.

(a)  

the curve on a phase diagram which represents the transition between liquid and solid states

(a)  

the curve on a phase diagram which represents the transition between gaseous and liquid states

(a)  

the curve on a phase diagram which represents the transition between gaseous and solid states.

(a)  

A system is a homogeneous mixture of substances that melts or solidifies at a single temperature lower than each constituent's melting point.

(a)  

________, a British physicist and chemist, invented the word eutectic in _______.

(a)  

is defined as a mixture of two or more components which usually do not interact to form a new chemical compound but, which at certain ratios, inhibit the crystallization process of one another resulting in a system having a lower melting point than either of the components

(a)  

(a) The components must be miscible in the liquid state and often immiscible in the solid-state.(b) Close contact between eutectic forming materials is needed for contact-induced melting point depression.(c) Chemical groups that can interact to form physical bonds, such as intermolecular hydrogen bonding, etc.(d) Molecules that follow modified VantHoff's law.

(a)  

is the lowest possible melting temperature, for all mixture ratios of the constituent compounds in a eutectoid. The super-lattice will expel all of its components at this temperature, and the entire eutectic structure will dissolve into a jelly. In contrast, in a non-eutectic mixture, each part can solidify into a lattice at its particular temperature before the whole substance solidifies. Where a eutectoid is a stable mixture that occurs when two or more molten metals are cooled to a certain temperature.

(a)  

During the crystallization process, a mixture of the components is created, resulting in the product behaving as a single unit. The materials freeze into a close-knit crystal mixture and melt at the same time, with no distinction (Lane, 1989). Eutectics are organic and/or inorganic chemical mixtures. As a result, eutectics may be rendered as organic-organic, inorganic-inorganic, or organic-inorganic blends.

(a)