This document provides an introduction to chemistry concepts including solutions, vapor pressure, Raoult's law, and colligative properties. It defines a solution as a homogeneous mixture and discusses solvents and solutes. It then explains vapor pressure and how it relates to Raoult's law for binary solutions. Finally, it discusses the four colligative properties - lowering of vapor pressure, elevation of boiling point, depression of freezing point, and osmotic pressure - and provides examples of Henry's law in daily life like carbonated drinks and decompression sickness in divers.
4. INTRODUCTION
WHAT IS SOLUTION, TYPE OF SOLN.
VAPOUR PRESSURE
MATHEMATICAL FORMULA ,GRAPH
RAOULT”S LAW
RELATION B/W V.P $ RAOULT’S LAW
COLLIGATIVE PROPERTY
ALL FOUR PROPERTIES
HENRY”S LAW
ITS APPLICATIONS IN DAILY LIFE
CONTENT
5. INTRODUCTION
A Solution is another name of homogeneous mixture. A
mixture as a material composed of two or more substances and
a hom0geneous mixture of two or more substance is called a
SOLUTION. A solution prepared by mixing two substances is
called binary solution whereas a solution obtained on mixing
three mixtures is called ternary solution.
The major component of solution ,called the SOLVENT ,is
typically the same phase as solution itself. Each minor
component of solution is called the SOLUTE .
6. SOLVENT SOLUTE EXAMPLE
1. SOLID SOLID BRASS
LIQUID AMALGAM
GAS GAS MASK
2. LIQUID SOLID WATER+SUGAR
LIQUID WATER+ETHANOL
GAS WATER+AMMONIA
3. GAS SOLID SMOKE
LIQUID MOISTURE
GAS AIR
7. VAPOUR PRESSURE
.
The vapour pressure of a liquid is
defined as the pressure exerted by its
vapour phase in equilibrium with liquid
phase at a given temperature. The
vapour pressure is also defined as “the
pressure exerted by vapours of solvent
and solute in equilibrium with the liquid
phase is called vapour pressure of
solution” THE VAPOUR PRESSURE IS
GIVEN AS:
p[solution]=p[solvent]+p[solute]
8. •Raoult’s law states that a solvent’s partial vapour
pressure in a solution (or mixture) is equal or
identical to the vapour pressure of the pure solvent
multiplied by its mole fraction in the solution
According to raoult’ law: p(solvent) = p(solvent)
x(solvent) ; where x denotes mole fraction
Also p(solute)= p (solute) x(solute)
9. An azeotrope is defined as a homogeneous mixture which boils at a constant temperature without
change in its composition . The term azeotrope is a combination of zein = to boil and atrope =
unchanging . In an azeotropic mixture the composition of the liquid phase is the same as the
composition of the vapour phase .
xA=yAAND xB=yB
BUT xA is not equal to xB and yA is not
equal to yB
10. The properties of a solution which depends only on the relative number of moles of solute but are
independent of their nature, are called colligative properties .
TYPES OF COLLIGATIVE PROPERTIES
• There are four colligative properties :
1. LOWERING OF VAPOUR PRESSURE
2.ELEVATION OF BOILING POINT
3.DEPRESSION OF FREEZING POINT
4.OSMOTIC PRESSSURE
11. The difference between the boiling point of a solution containing a nonvolatile solute and the boiling
point of a pure solvent is defined as the elevation of boiling point . It id denoted by delta Tb . That is:
deltaTb=Tb –T b = Elevation of boiling point
12. The difference between the freezing point of the pure solvent and freezing point of the solution
is defined as the depression of freezing point. It is denoted by deltaTf . That is,
deltaTf = T f – Tf = Depression of freezing point
13. 01 HENRY’S LAW
The partial pressure of a gas and its mole fraction in a
solution are related by henry’ s law . This law states that
the mole fraction of a gas dissolved in a liquid is directly
proportional to the partial pressure of the gas above its
saturated solution .
xB is directly proportional to pB =K * pB
Where, pB = partial pressure of the gas
above the solution
xB = mole fraction of gas dissolved in the
liquid
KH = henry’s law constant
14. 1.PREPARATION OF CARBONATED SOFT DRINKS :
Carbon dioxide is dissolved under high pressure in
boiled soft drinks . When the cap of he bottle is
removed, the pressure of carbon dioxide above the
soda is reduced consequently , the solubility of
carbon dioxide and the bubbles of the gas come
out.
15. 2. DECOMPRESSION SICKNESS EXPERIENCED BY DEEP SEA DIVERS :
The painful and even fatal effect effect called decompression sickness or
the bends experienced by deep sea divers is due to the change in solulility
of gases in blood .