BÀI TẬP BỔ TRỢ TIẾNG ANH 11 THEO ĐƠN VỊ BÀI HỌC - CẢ NĂM - CÓ FILE NGHE (FRIE...
1.state of matter 2017
4. Which factor decide the physical state
of matter?
• Intermolecular force – Pressure
> Or < change the state of matter. Eg. Solid Co2.
• Thermal energy – Temperature
T > K.E > Electron motion > vibration of particle
10. Intermolecular and intramolecular
Interactions
Intermolecular force also called van dar waal force.
Force of attraction between neighboring molecules,
situated at a distance much closer in comparison
with their molecular diameter. Eg. H – Cl.
Hold the constituent atoms of a molecule intact in
the molecule and result due to the formation of
chemical bonds between the atoms inside the
molecule. <10-10. Eg- H-O-H.
29. Why B.P of inert gases increase with
the increase in atomic mass ?
• Non polar
• Attraction based on
London force.
• If At. Mass > At no. >
At. Size > attraction >.
30. Dipole Dipole interaction
The force of attraction between
neighboring molecule (eg. HCl)
having permanent dipole moment.
91. Critical Temperature
It (Tc) is the maximum temperature
at which a gas can be liquefied i.e.
the temperature above which a gas
can’t exist as liquid.
Critical Pressure
It is the minimum pressure required to
cause liquefaction at Tc.
Critical Volume
It is the volume occupied by one mol of a
gas at Tc and Pc .
92. Properties of liquid
• The liquid molecules are relatively close together
• The intermolecular forces of attraction in case of
liquids are much larger than in gases.
• Unlike gases, liquids have a definite volume
although no definite shape (similarity with gases).
• The molecules are in constant random motion.
• The average kinetic energy of molecules in a given
sample is proportional to the absolute temperature.
93. Vapour Pressure
“The pressure exerted by the
vapour present above the liquid
in equilibrium with the liquid at
that temperature. “
94. Viscosity
• The force of friction between layer of liquid is
called viscosity.
• The force existing between the two consecutive
layers of fluids due to their velocity gradient is
called viscous force.
Hinweis der Redaktion
repulsion
repulsion
Thermal energy
comparison
+ shift twoard –ve.
electrostatic unit of charge, esu
Intermolecular Forces
Intermolecular forces are forces between molecules and intramolecular forces act within molecules
Intermolecular forces are the forces that exist between molecules. Don't confuse these with intramolecular forces, which are the strong forces that keep a molecule together. 'Intra' means inside, so these are the inside forces in a molecule. 'Inter' means between, so these are the forces between molecules. To remember the difference between inter and intra, I always think of 'interstate.' In every state there is an interstate road that goes across more than one state, like Interstate 80 that runs from the Pacific Ocean in California to the Atlantic Ocean in New York. Intermolecular forces are weaker than intramolecular forces but still very important. The two intermolecular forces we are talking about in this video include dipole-dipole and ion-dipole.
London dispersion force is the weak intermolecular force that results from the motion of electrons that creates temporary dipoles in molecules. The London dispersion force is sometimes called a 'van der Waals force.' Van der Waals force is a general term that describes any attractive intermolecular force between molecules and includes both the London dispersion force and the dipole-dipole force discussed elsewhere.
London Dispersion Force
You know that every atom and molecule has electrons and that these electrons are in constant motion. At any one instant in time, these electrons can be more towards one side of a molecule than another. When the electrons are concentrated more at one end of a molecule, that end becomes slightly negative. The other end, where the electrons are not as concentrated, becomes slightly positive. At this instant, this molecule is a temporary dipole. This dipole can encourage a nearby molecule to also become dipole because the negative side of the first molecule will cause the electrons to run away on the other molecule (since negative (-) detests negative (-)).
Now these two adjacent dipoles created from the movement of electrons are attracted to each other. This very weak intermolecular force is called London dispersion force.
Dipole-Dipole Forces
A dipole is a molecule that has both positive and negative regions. Although we talk as though electrons distribute their time evenly among all atoms in a molecule, some elements have more affinity for the electrons than others, and they hang out around that atom more. We also talk about these molecules being polar. Apolar molecule is a molecule with a slightly positive side and a slightly negative side. I always think about the North and South Poles of the earth to help me remember what a polar molecule is. A dipole-dipole force is when the positive side of a polar molecule attracts the negative side of another polar molecule. In order for this kind of bond to work, the molecules need to be very close to each other, like they are in a liquid.
An ion-dipole force is just what its name says. It is a force between an ion and a dipole molecule. Remember that an ion is an atom that has gained or lost one or more electrons and therefore has a negative or positive charge. A cation is an atom that has lost a valence electron and therefore has more positive protons than negative electrons, so it is positively charged. An anion is an atom that has gained a valence electron and is negatively charged.
So knowing that a dipole molecule has a slight charge on either side and that ions have charges, either negative or positive, you can understand how these would bond together. Cations would be attracted to the negative side of a polar molecule and anions would be attracted to the positive side.
Examp dipole induce dipole
Magnetic ki tarha temporary charge prodcution.
Also called dipole dipole interaction
Aniline,
Gaseous State: Gas Laws - Lesson Summary
Among the known 117 elements, only 11 elements are in the gaseous state at room temperature and pressure. The gaseous state is the simplest form of matter.
Properties: • Gases have no definite shape and volume and hence assume the volume and shape of the container. • Gases are highly compressible. • Gases exert equal pressure in all directions. • Gases intermix equally and completely in all proportions. • Gases have lower density than solids and liquids.The study of the behavior of gases has led to some important generalisations called the Gas Laws.
Boyles law
P α 1/V (at const temperature)
PV= k ( proportionality constant)
P1V1 = P2V2
Charelew definarion
This line line is called isobar. If we put this value in formula we get zero voulme. This indicate that volume of gas is zero at -273C. This temp. is called absolute zero.
Volume line is called isochore.
Temp and pressure constant v = n n. of mole
The relationship between volume, number of moles, pressure and temperature is described by three laws. They are Boyle's Law, Charles' Law and Avogadro's Law.
Boyle's Law describes the relationship between pressure and volume. It states that volume is inversely proportional to pressure at constant temperature and number of moles.
Charles' Law describes the relationship between temperature and volume. It states that volume is directly proportional to temperature at constant pressure and number of moles.
Avogadro's Law describes the relationship between volume and number of moles. It states that at constant pressure and temperature, the volume of a gas is directly proportional to the number of moles present in the gas.
Ideal gas equation can be obtained by combining these laws,
Boyle's law V ∝ 1/P (T, n)
Combined gas law
Gaseous State: Dalton's Law Of Partial Pressure - Lesson Summary
In 1807, John Dalton studied the pressure exerted by a mixture of non-reacting gases enclosed in a vessel.
According to Dalton's law of partial pressures, "The total pressure exerted by a mixture of two or more non-reacting gases enclosed in a vessel at a given temperature is equal to the sum of the partial pressures exerted by individual gases if they were enclosed separately in that vessel at the same temperature.
Mathematically it can be written as:
Ptotal = p1 + p2 + p3
Ptotal = total pressure exerted by the mixture of gases.
p1, p2, p3 are partial pressures of individual gases.
On applying the ideal gas equation,
Gaseous State: Kinetic Molecular Theory - Lesson Summary
In order to understand the behavior of gases at the molecular level, scientists developed a theoretical model called Kinetic Molecular Theory (KMT) or Microscopic Model of Gases.
Kinetic Molecular Theory assumptions:
a) Gases consist of very large number of extremely small particles called molecules, which are in constant, continuous, random and straight-line motion.
b) During their motion, they collide with each other and against the walls of the container. The pressure exerted by the gas is due to the bombardment of its molecules on the walls of the container.
c) The molecules of a gas are separated from each other by great distances .Hence the actual volume of all the molecules of the gas is negligible when compared to the total volume occupied by the gas.
d) Attractive and repulsive forces between the molecules of a gas are negligible as they are much away from each other.
This 5 assumption show the behavior of molecule of gas. Lets discusss each asumption in detail.
Extermely small particle gas called molecule. This gas molecule can be const cont random etc. during motion gas particle colloid each other. So pressure came from particle colloided.
Jo bhi gas pe pressure lag raha hai wo collision se hai. Jitana less volume hoga utna zyada collision hoga.
The molecule of gas is seprated each other by great distance. So the actual volume of all gases are negegible. When compared the total volume occupy by the gas.
This assumption is true when gas highly compressed there volume is negligible.
Attractive and repulsive force are neglibile bcose they away from eacth other. Gas expand and take entire space. Bcose of this conncetion weak. So attration negligible.
When 2 gas molecule colloid no energy release or absorbed. Theat means they bounce after. Neither during collision molecule slow down and settle down.
This asumption say when temp increase gas molecule movement increase. i.e average K.E > T.
Bsed on this asumption the equation of gas is given.
Lets us now understand gas law with kinetic molecular theory of gas.
Boyles law p α V. i.e gas molecule collision se pressure hona. That mean if voluem less pressure increase bcose collision increase.
T=V, i.e when we heat gas molcule their K.E increase their speed increase there collision highly increasa as a result piston push outward. Volume of a gas increases.