Physical Chemistry
Dr Eman Badr
Professor of Medical Biochemistry and
Molecular Biology
Faculty of Medicine- Menoufia University
IPC-Solutions-Borders
What is the Matter
• Matter is any substance that has mass and takes up
space by having volume.
•
• Classification of Matter
•
• Any matter can exist in one of 3 States
(a) Gas (b) Liquid (c) Solid
Chemistry-Borders IPC-Solutions-Borders
Classification of Matter
1. Solid matter is composed of tightly
packed particles. A solid will retain its
shape; the particles are not free to move
around.
2. Liquid matter is made of more loosely
packed particles. It will take the shape of
its container. Particles can move about
within a liquid, but they are packed
densely enough that volume is
maintained.
3. Gaseous matter is composed of
particles packed so loosely that it has
neither a defined shape nor a defined
volume. A gas can be compressed.
Types of Matters
• A pure substance is a single kind of matter that cannot be
separated into other kinds of matter by any physical means.
• A mixture (not pure substance) is a material made up of two
or more different chemical substances which are not
chemically bonded. can usually be separated back into its
original components.
Matter Flowchart
MATTER
Can it be physically
separated?
Homogeneous
Mixture
(true solution)
Heterogeneous
Mixture Compound Element
MIXTURE PURE SUBSTANCE
yes no
Can it be chemically
decomposed?
no
yes
Is the composition
uniform?
no
yes
Colloids Suspensions
IPC-Solutions-Borders
Solutions
Solutions, in chemistry, are homogeneous
mixtures of two or more substances.
The substance present in largest quantity usually
is called the solvent.
The substance that is present in smallest quantity
is said to be dissolved and is called the solute.
The solute can be either a gas, a liquid, or a
solid.
Solution
• a mixture of two or more substances that is
composed of solutes and solvents
the substance in the smallest
amount and the one that
dissolves in the solvent
the substance in the larger
amount that dissolves the
solute
(solute) Water
(solvent)
(solution)
Salt water is
considered a
solution. How
can it be
physically
separated?
Expression of concentration of
solutions
Chemistry-Borders IPC-Solutions-Borders
MOLAR VS MOLAL
• One mole of a solute (MW) dissolved
and made up in 1 liter of solvent
(1000ml) is a 1M (one molar solution)
• One mole of a solute (MW) dissolved
in 1 kilogram of solvent (1000g) is a
1m (one molal solution)
Normal solutions (N)
• These are solutions containing one gram
equivalent (g Eq) of the substance per
liter. One gram equivalent is the equivalent
weight of the substance expressed in
grams.
Types of solutions
Chemistry-Borders IPC-Solutions-Borders
1-True Solutions(crystalloids)
• Very small particle size: .01 nm-1 nm
• Do not separate upon standing
• Are transparent
• Cannot be separated by filtration
• Particles do not display the Tyndall Effect:
the particles are too small to scatter light
2- Colloidal soultions
• A heterogeneous mixture
• May or may not be transparent
• Medium particle size: 1 nm -200 nm
• Do not separate upon standing
• Cannot be separated by filtration
• Particles display the Tyndall Effect: the particles
are large enough to scatter light
Examples of Colloids
• Gelatin in H2O
• Milk
• Clouds
3- Suspensions
• A heterogeneous mixture
• Are not transparent
• Large particle size: over 200 nm
• Particles settle out
• Can be separated by filtration
• May or may not display the Tyndall Effect
Examples of Suspensions
• Clay in H2O
• Cooking oil in H2O
• Spoiled milk
17
Hydrophilic and Hydrophobic Colloids
Hydrophilic: water-loving
(emulsoids)
Hydrophobic: water-fearing
(suspensoids)
Stabilization of a hydrophobic colloid
Types of colloids
Emulsoids Suspensoids
Lyophilic (solvent loving). Lyophobic (solvent fearing).
Stabilized by the presence of
charges and a film of solvent
around solute particles.
Stabilized by the presence of charges
around solute particles only.
Thus precipitation is difficult. Easily precipitated.
Can be redissolved by adding
excess solvent.
If precipitated, they cannot be
redissolved.
Have higher viscosity and lower
surface tension than their solvent.
Have the same viscosity and surface
tension as their solvent.
Some emulsions form gels. Cannot form gels.
Ex; starch and protein in water. Ex; gold and ferric hydroxide in water.
Properties of Colloids
1-Tyndall effect
– when a strong beam of light is
passed through a colloidal
sol, the path of light is
illuminated (a visible cone
formed).
- This phenomenon resulting
from the scattering of light by
the colloidal particles.
Properties of Colloids
2-Brownian motion
- The zig-zag movement of colloidal particles
continuously and randomly.
• This brownian motion arises due to the
uneven distribution of the collisions
between colloid particle and the solvent
molecules.
- Brownian movement was more rapid for
smaller particles.
- It decrease with increase the viscosity of
the medium.
3- Dialysis:
- Semipermeable cellophane
membrane prevent the
passage of colloidal particles,
yet allow the passage of
small molecules or electrolytes.
4-ULTRACENTRIFUGATION
Involves the use of
the centrifugal force.
More dense
components migrate
away. Solid particles
remain on the bottom.
5-Precipitation of colloids
• This is obtained by:
1- Addition of concentrated electrolytes
- The precipitation power is directly related to the hydration of
the ion and its ability to separate water molecules from
colloidal particles
2- addition of Alcohol + diluted electrolytes
.
6-ADSORPTION and Elution
Adsorption is the process in which matter is
extracted from one phase and
concentrated at the surface of a second
phase. (Interface accumulation).
elution is the process of extracting one
material from another by washing with a
solvent; as in washing of loaded ion-
exchange resins to remove captured ions
Adsorption Mechanism
– 2) Chemical adsorption
• Results from a chemical interaction between the
adsorbate and adsorbent. Therefore formed bond
is much stronger than that for physical adsorption
• Heat liberated during chemisorption is in the range
of 20-400 kj/g mole
ENVE542 GYTE Çevre Müh. 25
2024/2/18 Aerosol & Particulate Research Lab 25
7- Gelation
• Emulsoids can form gels (change from
liquid state to semisolid state) by
• Lowering the temperature.
• Increasing the concentration.
• Changing the PH.

Physical_ Chemistry_ Lecture_ 1111 .ppt

  • 1.
    Physical Chemistry Dr EmanBadr Professor of Medical Biochemistry and Molecular Biology Faculty of Medicine- Menoufia University IPC-Solutions-Borders
  • 2.
    What is theMatter • Matter is any substance that has mass and takes up space by having volume. • • Classification of Matter • • Any matter can exist in one of 3 States (a) Gas (b) Liquid (c) Solid Chemistry-Borders IPC-Solutions-Borders
  • 3.
    Classification of Matter 1.Solid matter is composed of tightly packed particles. A solid will retain its shape; the particles are not free to move around. 2. Liquid matter is made of more loosely packed particles. It will take the shape of its container. Particles can move about within a liquid, but they are packed densely enough that volume is maintained. 3. Gaseous matter is composed of particles packed so loosely that it has neither a defined shape nor a defined volume. A gas can be compressed.
  • 4.
    Types of Matters •A pure substance is a single kind of matter that cannot be separated into other kinds of matter by any physical means. • A mixture (not pure substance) is a material made up of two or more different chemical substances which are not chemically bonded. can usually be separated back into its original components.
  • 5.
    Matter Flowchart MATTER Can itbe physically separated? Homogeneous Mixture (true solution) Heterogeneous Mixture Compound Element MIXTURE PURE SUBSTANCE yes no Can it be chemically decomposed? no yes Is the composition uniform? no yes Colloids Suspensions IPC-Solutions-Borders
  • 6.
    Solutions Solutions, in chemistry,are homogeneous mixtures of two or more substances. The substance present in largest quantity usually is called the solvent. The substance that is present in smallest quantity is said to be dissolved and is called the solute. The solute can be either a gas, a liquid, or a solid.
  • 7.
    Solution • a mixtureof two or more substances that is composed of solutes and solvents the substance in the smallest amount and the one that dissolves in the solvent the substance in the larger amount that dissolves the solute (solute) Water (solvent) (solution) Salt water is considered a solution. How can it be physically separated?
  • 8.
    Expression of concentrationof solutions Chemistry-Borders IPC-Solutions-Borders
  • 9.
    MOLAR VS MOLAL •One mole of a solute (MW) dissolved and made up in 1 liter of solvent (1000ml) is a 1M (one molar solution) • One mole of a solute (MW) dissolved in 1 kilogram of solvent (1000g) is a 1m (one molal solution)
  • 10.
    Normal solutions (N) •These are solutions containing one gram equivalent (g Eq) of the substance per liter. One gram equivalent is the equivalent weight of the substance expressed in grams.
  • 11.
  • 12.
    1-True Solutions(crystalloids) • Verysmall particle size: .01 nm-1 nm • Do not separate upon standing • Are transparent • Cannot be separated by filtration • Particles do not display the Tyndall Effect: the particles are too small to scatter light
  • 13.
    2- Colloidal soultions •A heterogeneous mixture • May or may not be transparent • Medium particle size: 1 nm -200 nm • Do not separate upon standing • Cannot be separated by filtration • Particles display the Tyndall Effect: the particles are large enough to scatter light
  • 14.
    Examples of Colloids •Gelatin in H2O • Milk • Clouds
  • 15.
    3- Suspensions • Aheterogeneous mixture • Are not transparent • Large particle size: over 200 nm • Particles settle out • Can be separated by filtration • May or may not display the Tyndall Effect
  • 16.
    Examples of Suspensions •Clay in H2O • Cooking oil in H2O • Spoiled milk
  • 17.
    17 Hydrophilic and HydrophobicColloids Hydrophilic: water-loving (emulsoids) Hydrophobic: water-fearing (suspensoids) Stabilization of a hydrophobic colloid
  • 18.
    Types of colloids EmulsoidsSuspensoids Lyophilic (solvent loving). Lyophobic (solvent fearing). Stabilized by the presence of charges and a film of solvent around solute particles. Stabilized by the presence of charges around solute particles only. Thus precipitation is difficult. Easily precipitated. Can be redissolved by adding excess solvent. If precipitated, they cannot be redissolved. Have higher viscosity and lower surface tension than their solvent. Have the same viscosity and surface tension as their solvent. Some emulsions form gels. Cannot form gels. Ex; starch and protein in water. Ex; gold and ferric hydroxide in water.
  • 19.
    Properties of Colloids 1-Tyndalleffect – when a strong beam of light is passed through a colloidal sol, the path of light is illuminated (a visible cone formed). - This phenomenon resulting from the scattering of light by the colloidal particles.
  • 20.
    Properties of Colloids 2-Brownianmotion - The zig-zag movement of colloidal particles continuously and randomly. • This brownian motion arises due to the uneven distribution of the collisions between colloid particle and the solvent molecules. - Brownian movement was more rapid for smaller particles. - It decrease with increase the viscosity of the medium.
  • 21.
    3- Dialysis: - Semipermeablecellophane membrane prevent the passage of colloidal particles, yet allow the passage of small molecules or electrolytes.
  • 22.
    4-ULTRACENTRIFUGATION Involves the useof the centrifugal force. More dense components migrate away. Solid particles remain on the bottom.
  • 23.
    5-Precipitation of colloids •This is obtained by: 1- Addition of concentrated electrolytes - The precipitation power is directly related to the hydration of the ion and its ability to separate water molecules from colloidal particles 2- addition of Alcohol + diluted electrolytes
  • 24.
    . 6-ADSORPTION and Elution Adsorptionis the process in which matter is extracted from one phase and concentrated at the surface of a second phase. (Interface accumulation). elution is the process of extracting one material from another by washing with a solvent; as in washing of loaded ion- exchange resins to remove captured ions
  • 25.
    Adsorption Mechanism – 2)Chemical adsorption • Results from a chemical interaction between the adsorbate and adsorbent. Therefore formed bond is much stronger than that for physical adsorption • Heat liberated during chemisorption is in the range of 20-400 kj/g mole ENVE542 GYTE Çevre Müh. 25 2024/2/18 Aerosol & Particulate Research Lab 25
  • 26.
    7- Gelation • Emulsoidscan form gels (change from liquid state to semisolid state) by • Lowering the temperature. • Increasing the concentration. • Changing the PH.