The document discusses nuclear chemistry and nuclear reactions. It defines nuclear chemistry as the study of nuclear changes in atoms, which are the source of radioactivity and nuclear power. There are two main types of nuclear reactions - artificial transmutation induced by bombarding atoms and natural transmutation that occurs spontaneously. Nuclear fission and fusion reactions are also described, where fission is the splitting of heavy nuclei and fusion is the combining of light nuclei. Key components of nuclear reactors like fuel, moderator, control rods and coolants are outlined. The document also discusses atomic bombs and how they work by achieving supercritical mass through compressing or combining subcritical masses. Applications of radioisotopes as tracers in chemical investigations are briefly mentioned.
It contains the basic principle of Mossbauer Spectroscopy.
Recoil energy, Dopler shift.
The instrumentation of Mossbauer Spectroscopy.
Hyperfine interactions.
First part of Statistical Thermodynamics includes: Introduction, Ensembles, Types of Ensembles, Thermodynamic Probability, Boltzmann Distribution, Lagrange's Undetermined Multipliers, Partition Function, Types of Partition Functions, Thermodynamic Properties in terms of partition Function, Heat Capacity, Heat Capacity of Monoatomic Solids, Dulong-Petit law, Einstein Model for solids, 3rd Law and Residual Entropy
It contains the basic principle of Mossbauer Spectroscopy.
Recoil energy, Dopler shift.
The instrumentation of Mossbauer Spectroscopy.
Hyperfine interactions.
First part of Statistical Thermodynamics includes: Introduction, Ensembles, Types of Ensembles, Thermodynamic Probability, Boltzmann Distribution, Lagrange's Undetermined Multipliers, Partition Function, Types of Partition Functions, Thermodynamic Properties in terms of partition Function, Heat Capacity, Heat Capacity of Monoatomic Solids, Dulong-Petit law, Einstein Model for solids, 3rd Law and Residual Entropy
For UG students of All Engineering Branches (Mechanical Engg., Chemical Engg., Instrumentation Engg., Food Technology) and PG students of Chemistry, Physics, Biochemistry, Pharmacy
The link of the video lecture at YouTube is
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NQR - DEFINITION - ELECTRIC FIELD GRADIENT - NUCLEAR QUADRUPOLE MOMENT - NUCLEAR QUADRUPOLE COUPLING CONSTANT - PRINCIPLE OF NQR - ENERGY OF INTERACTION - SELECTION RULE - FREQUENCY OF TRANSITION - APPLICATIONS
Electron Spin Resonance (ESR) SpectroscopyHaris Saleem
Electron Spin Resonance Spectroscopy
Also called EPR Spectroscopy
Electron Paramagnetic Resonance Spectroscopy
Non-destructive technique
Applications
Extensively used in transition metal complexes
Deviated geometries in crystals
For UG students of All Engineering Branches (Mechanical Engg., Chemical Engg., Instrumentation Engg., Food Technology) and PG students of Chemistry, Physics, Biochemistry, Pharmacy
The link of the video lecture at YouTube is
https://www.youtube.com/watch?v=t3QDG8ZIX-8
NQR - DEFINITION - ELECTRIC FIELD GRADIENT - NUCLEAR QUADRUPOLE MOMENT - NUCLEAR QUADRUPOLE COUPLING CONSTANT - PRINCIPLE OF NQR - ENERGY OF INTERACTION - SELECTION RULE - FREQUENCY OF TRANSITION - APPLICATIONS
Electron Spin Resonance (ESR) SpectroscopyHaris Saleem
Electron Spin Resonance Spectroscopy
Also called EPR Spectroscopy
Electron Paramagnetic Resonance Spectroscopy
Non-destructive technique
Applications
Extensively used in transition metal complexes
Deviated geometries in crystals
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1. Nuclear Chemistry
Introduction: -
The study of the nuclear changes in an atom is termed as nuclear
chemistry. Nuclear changes are source of radioactivity & nuclear power. That’s
why nuclear chemistry is very important branch of chemistry.
The process in which atom of one element is converted into atom of
another element is called transmutation. Transmutation may take place
naturally or brought about artificially.
uncontrollable disintegration occurs by emission of active radiations from an
unstable atomic nucleus
radiations is called radioactive substance.
Nuclear Reaction: -
The reaction in which the nucl
called nuclear reaction.
According to Bethe above reaction can be represented as
i.e. Target element (Projectile, Emission) Daughter element.
* The particle used for bombardment in nuclear reaction is called Projectile.
* The element which is bombarded by Projectile is called Target element.
* The product obtained in nuclear reaction is called R
element.
* The particle emitted during
Energetic of Nuclear Reaction
loss of energy.
Nuclear Reaction in which energy i
reaction.
Nuclear Chemistry Prof. Jadhav Swapnil S.
The study of the nuclear changes in an atom is termed as nuclear
Nuclear changes are source of radioactivity & nuclear power. That’s
nuclear chemistry is very important branch of chemistry.
The process in which atom of one element is converted into atom of
another element is called transmutation. Transmutation may take place
naturally or brought about artificially. Phenomenon of sponta
uncontrollable disintegration occurs by emission of active radiations from an
is called radioactivity. The substance that emits
called radioactive substance.
he reaction in which the nucleus of an atom undergoes transmutation is
According to Bethe above reaction can be represented as 9
Be (α, n)
i.e. Target element (Projectile, Emission) Daughter element.
used for bombardment in nuclear reaction is called Projectile.
is bombarded by Projectile is called Target element.
in nuclear reaction is called Recoil nucleus or Daughter
ring nuclear reaction is called Emission.
Energetic of Nuclear Reaction: - Nuclear Reactions associat
Nuclear Reaction in which energy is absorbed is called endoergic n
Prof. Jadhav Swapnil S.
The study of the nuclear changes in an atom is termed as nuclear
Nuclear changes are source of radioactivity & nuclear power. That’s
The process in which atom of one element is converted into atom of
another element is called transmutation. Transmutation may take place
henomenon of spontaneous and
uncontrollable disintegration occurs by emission of active radiations from an
is called radioactivity. The substance that emits
ergoes transmutation is
Be (α, n) 12
C.
i.e. Target element (Projectile, Emission) Daughter element.
used for bombardment in nuclear reaction is called Projectile.
is bombarded by Projectile is called Target element.
ecoil nucleus or Daughter
nuclear reaction is called Emission.
Nuclear Reactions associated with gain or
s absorbed is called endoergic nuclear
2. Nuclear Reaction in which energy
reaction.
In Nuclear Reaction change in energy is large and calculated by Einstein
equation. E = m C2
1 amu = 931 MeV 1 MeV = 9.648 × 10
Types of Nuclear Reaction:
1) Artificial Transmutation 2) Natural Transmutation
1) Artificial Transmutation
i) Artificial Transmutation or Artificial disintegration:
When the transmutation is done by artificial means is called Artificial
Transmutation or disintegration.
Or the conversion of one element into another element by artificial means is
called Artificial Transmutation or disintegration.
First Artificial Transmutation was recognized, described and reported by
Rutherford in 1919.
E.g. Using various projectiles
Nuclear Reaction in which energy is released is called exoergic n
In Nuclear Reaction change in energy is large and calculated by Einstein
1 amu = 931 MeV 1 MeV = 9.648 × 107
KJ/mol
Types of Nuclear Reaction: -
1) Artificial Transmutation 2) Natural Transmutation
1) Artificial Transmutation
i) Artificial Transmutation or Artificial disintegration: -
When the transmutation is done by artificial means is called Artificial
ransmutation or disintegration.
the conversion of one element into another element by artificial means is
called Artificial Transmutation or disintegration.
First Artificial Transmutation was recognized, described and reported by
projectiles various transmutations are carried out
is released is called exoergic nuclear
In Nuclear Reaction change in energy is large and calculated by Einstein
When the transmutation is done by artificial means is called Artificial
the conversion of one element into another element by artificial means is
First Artificial Transmutation was recognized, described and reported by
transmutations are carried out as
3. ii) Artificial radioactivity or induced radioactivity:
The radioactivity produced by process of artificial atomic transmutation
is called artificial radioactivity or induced radioactivity.
Artificial radioactivity first discovered by Irene Curie
husband F. Joliot awarded by Nobel
e.g. The bombardment of α particle on Aluminium forms radioactive
Phosphorous which emits po
“The process of converting stable nuclei into unstable radioactive nuclei
by artificial transmutation is called artificial radioactivity.”
e.g.
iii) Projectile capture reaction:
The Nuclear Reaction in which the projectile is captured with
γ emission is called Projectile
The Projectile captured is usually neutron but for low masses nuclei proton is
also captured.
ii) Artificial radioactivity or induced radioactivity: -
The radioactivity produced by process of artificial atomic transmutation
radioactivity or induced radioactivity.
Artificial radioactivity first discovered by Irene Curie
husband F. Joliot awarded by Nobel Prize in 1935.
he bombardment of α particle on Aluminium forms radioactive
Phosphorous which emits positron to form Silicon.
process of converting stable nuclei into unstable radioactive nuclei
by artificial transmutation is called artificial radioactivity.”
iii) Projectile capture reaction: -
The Nuclear Reaction in which the projectile is captured with
called Projectile capture reaction.
The Projectile captured is usually neutron but for low masses nuclei proton is
The radioactivity produced by process of artificial atomic transmutation
Artificial radioactivity first discovered by Irene Curie-Joliot and her
he bombardment of α particle on Aluminium forms radioactive
process of converting stable nuclei into unstable radioactive nuclei
The Nuclear Reaction in which the projectile is captured with or without
The Projectile captured is usually neutron but for low masses nuclei proton is
4. iv) Projectile capture particle emission reaction:
The Nuclear Reaction in which the projectile is captured
another particle is called Projectile capture particle emission reaction.
Majority of nuclear reactions are come under this category.
v) Nuclear fission reaction:
a) The reaction in which heavy nucleus is broken down into two or more nuclei
having medium masses with liberation of large
nuclear fission reaction.
b) When the nuclei with mass no. greater than 200 are bomba
or other projectile with sufficient energy
c) Fission reaction usually accompanied by neutrons.
d) First nuclear reaction discovered by German scientist Otto
Strassman in 1938.
e) During fission reaction 2
which bring breaking of
chain reaction. (The chain reaction which continued without break is called
sustained or self propagated reaction.)
released.
capture particle emission reaction: -
The Nuclear Reaction in which the projectile is captured
another particle is called Projectile capture particle emission reaction.
Majority of nuclear reactions are come under this category.
Nuclear fission reaction: -
a) The reaction in which heavy nucleus is broken down into two or more nuclei
having medium masses with liberation of large amount of
b) When the nuclei with mass no. greater than 200 are bomba
or other projectile with sufficient energy undergoes fission process.
c) Fission reaction usually accompanied by neutrons.
First nuclear reaction discovered by German scientist Otto
reaction 2-3 neutrons are emitted called seco
next target nuclei and reaction is continued called
chain reaction. (The chain reaction which continued without break is called
sustained or self propagated reaction.). Due to this large am
The Nuclear Reaction in which the projectile is captured with emission of
another particle is called Projectile capture particle emission reaction.
a) The reaction in which heavy nucleus is broken down into two or more nuclei
amount of energy is called
b) When the nuclei with mass no. greater than 200 are bombarded by neutron
undergoes fission process.
First nuclear reaction discovered by German scientist Otto-Hahn and F.
3 neutrons are emitted called secondary neutrons
and reaction is continued called
chain reaction. (The chain reaction which continued without break is called
. Due to this large amount of energy is
5. f) The pair of fission product are classified as
And ii) heavier nuclei (Z = 130
g) Atom bomb works on the principal of fission reaction.
h) Energy produced in fission of 1 g U
of coal (8.22 × 107
KJ)
vi) Nuclear Fusion: -
a) The reaction in which two or more light nuclei fuse to form stable heavier
nucleus with liberation of very large energy is called nuclear fusion reaction.
b) The energy release during fus
reaction.
c) Fusion reaction takes
pressure hence called as thermonuclear reaction.
d) According to Bethe energy of sun where tem
by the proton-proton cycle as
f) The pair of fission product are classified as- i) lighter nuclei (Z = 80
nuclei (Z = 130-150)
bomb works on the principal of fission reaction.
h) Energy produced in fission of 1 g U-235 is equal to burning of 2.5 metric tons
a) The reaction in which two or more light nuclei fuse to form stable heavier
nucleus with liberation of very large energy is called nuclear fusion reaction.
release during fusion reaction is four times greater than fission
place at high temperature (4 × 10
pressure hence called as thermonuclear reaction.
d) According to Bethe energy of sun where temperature is 2 × 10
proton cycle as-
i) lighter nuclei (Z = 80-100)
equal to burning of 2.5 metric tons
a) The reaction in which two or more light nuclei fuse to form stable heavier
nucleus with liberation of very large energy is called nuclear fusion reaction.
greater than fission
place at high temperature (4 × 106 0
c) and high
perature is 2 × 107
k is generated
6. e) Fusion reaction are not suitable for man
f) Hydrogen bomb works on the principal of fusion reaction.
* Use of Uranium, Thorium and Plutonium for atomic
reactor: -
The energy released during nuclear reaction used for mankind is known
as atomic or nuclear energy. The cost of nuclear energy is comparable or even
less than traditional source. It has comparatively less pollution.
1. Thorium is used as blanket as it is fertile material (
the reactor atomic transmutation take place to form fissionable product as
2. 233
U and 235
U are fissionable nuclides.
3. Plutonium is not occurring n
natural uranium.
Thus 233
U, 235
U and 239
Pu are fissile and used atomic fuel.
e) Fusion reaction are not suitable for man-made experimentation.
f) Hydrogen bomb works on the principal of fusion reaction.
Note:
Use of Uranium, Thorium and Plutonium for atomic energy in nuclear
The energy released during nuclear reaction used for mankind is known
as atomic or nuclear energy. The cost of nuclear energy is comparable or even
less than traditional source. It has comparatively less pollution.
is used as blanket as it is fertile material (do not undergo fission
the reactor atomic transmutation take place to form fissionable product as
U are fissionable nuclides. 233
U is obtained from 232
3. Plutonium is not occurring naturally. The fissile Plutonium obtained from
Pu are fissile and used atomic fuel.
made experimentation.
energy in nuclear
The energy released during nuclear reaction used for mankind is known
as atomic or nuclear energy. The cost of nuclear energy is comparable or even
less than traditional source. It has comparatively less pollution.
do not undergo fission). In
the reactor atomic transmutation take place to form fissionable product as
232
Th.
aturally. The fissile Plutonium obtained from
7. * Typical power reactor
fuel, Moderator, Control road, Coolant.
Nuclear fuel:- 233
U, 235
U and
Moderator: - Moderators are used to slow down the fission neutrons. They are
made up of light elements and their compounds.
E.g. Heavy water, Paraffin, Beryllium, G
Control road: - Control rods are bars of metal such as cadmium, Boron. They
absorb neutrons and control the chain reaction.
Coolant: - Coolants are heat transfer agents. They transfer heat energy to heat
exchanger. E.g. liquid Sodium metal, CO
polyphenyls etc.
Shield or protective Chamber
components of reactor are enclosed in a chamber to avoid leaking of nuclear
radiations.
Atom Bomb: -
The basic condition for nuclear explosion
energetic neutron. The neutron production factor
Nuclear fission occurs when k>1, when k = 1 there is controlled chain
reaction. The efficiency of nuclear fission depends on weight and volume of
nuclear fuel used. The optimum size of the fuel at which the chain reaction
becomes self sustained is called critical size. (
mass). At subcritical mass,
fuel is less than critical mass i
more than critical mass is called over or super critical mass.
Typical power reactor: - The main components of the reactor are Nuclear
fuel, Moderator, Control road, Coolant.
U and 239
Pu are generally used as a fuel in power reactor.
Moderators are used to slow down the fission neutrons. They are
made up of light elements and their compounds.
Heavy water, Paraffin, Beryllium, Graphite etc.
Control rods are bars of metal such as cadmium, Boron. They
control the chain reaction.
Coolants are heat transfer agents. They transfer heat energy to heat
exchanger. E.g. liquid Sodium metal, CO2 gas, water, Heavy water air,
Shield or protective Chamber: - It is made up of cement and concrete. The
components of reactor are enclosed in a chamber to avoid leaking of nuclear
The basic condition for nuclear explosion is generation of highly
energetic neutron. The neutron production factor (k) is given by
Nuclear fission occurs when k>1, when k = 1 there is controlled chain
reaction. The efficiency of nuclear fission depends on weight and volume of
used. The optimum size of the fuel at which the chain reaction
becomes self sustained is called critical size. (And the mass is called critical
, k < 1 while at super critical mass, k > 1.
fuel is less than critical mass is called subcritical mass.)(The mass of fuel is
more than critical mass is called over or super critical mass.)
The main components of the reactor are Nuclear
Pu are generally used as a fuel in power reactor.
Moderators are used to slow down the fission neutrons. They are
Control rods are bars of metal such as cadmium, Boron. They
Coolants are heat transfer agents. They transfer heat energy to heat
Heavy water air,
It is made up of cement and concrete. The
components of reactor are enclosed in a chamber to avoid leaking of nuclear
is generation of highly
(k) is given by
Nuclear fission occurs when k>1, when k = 1 there is controlled chain
reaction. The efficiency of nuclear fission depends on weight and volume of
used. The optimum size of the fuel at which the chain reaction
the mass is called critical
t super critical mass, k > 1. (The mass of
The mass of fuel is
8. For nuclear explosion over critical and subcritical assembly is essential. It
is carried out by two techniques.
1. Assembling two subcritical m
quickly as possible.
2. Subcritical masses of fuel are subjected to high pressure
fuel increases, surface area decreases and thus rate of neutron production
accelerated leading to explosion.
* Schematic diagram for probable assembly for atom bomb:
It consist two subcritical masses
One is target while other one is projectile. The projectile is embedded in
explosive material like trinitrotoluene (TNT).
drives projectile 235
U into target
result instantaneous chain reaction start
For nuclear explosion over critical and subcritical assembly is essential. It
is carried out by two techniques.
1. Assembling two subcritical masses of fuel into an over critical mass as
masses of fuel are subjected to high pressure thereby density of
fuel increases, surface area decreases and thus rate of neutron production
accelerated leading to explosion.
diagram for probable assembly for atom bomb:
subcritical masses of pure 235
U at two ends of gun barrel.
One is target while other one is projectile. The projectile is embedded in
explosive material like trinitrotoluene (TNT). When the TNT is detonating, it
U into target 235
U. A supercritical mass is obtained
chain reaction start and the bomb explode.
For nuclear explosion over critical and subcritical assembly is essential. It
asses of fuel into an over critical mass as
thereby density of
fuel increases, surface area decreases and thus rate of neutron production
diagram for probable assembly for atom bomb: -
U at two ends of gun barrel.
One is target while other one is projectile. The projectile is embedded in
When the TNT is detonating, it
U. A supercritical mass is obtained. As a
explode.
9. Applications of Radioisotopes as tracers:-
1) Chemical investigation (Esterification): -
In ester hydrolysis by using water enriched in O18
isotope, it is found that
the acid only contains excess O18
as,
R--CO—OR’ + HO18
H R--CO—O18
H + R’—OH
This indicates that, -OR' bond is broken and O18
H from H2O18
takes the place of —
OR’
while H combine with —OR’ producing alcohol.
2) Structural determination of PCl5: -
1. The position of 5 chlorine atom in PCl5 is determined by isotopic labelling
method.
2. First PCl5 is synthesized by PCl3 and isotopic Cl2 (36
Cl2) and then hydrolysed.
i) PCl3 + 36Cl2*
PCl5*
ii) PCl5*
+ H2O POCl3 + 2HCl*
3. The reaction shows isotopic Cl*
atoms are remain in HCl and not in POCl3
which indicates in PCl5, two Cl atoms occupy different position than remaining
three Cl atoms.
4. Thus, in PCl5 3-Cl atoms are at equatorial plane and 2-Cl atoms are at
vertices.
5. This evidence confirms the Structural of PCl5 is trigonal bipyramidal.
3) Medical Application: - (Isotopic dilution method for determination of
volume of blood)
(a) Volume of blood can be determined by using isotopic dilution method. (b)
1 cm3
of blood of patient is withdraw and labelled with solution of 24
Na as NaCl
and its initial specific activity (S1) is measured in 0.1 cm3
. The remaining
labelled sample is reinserted (0.9 cm3
= y). (c) After 15 minutes once again 1
cm3
of blood of patient is withdraw and its initial specific activity (S2) is
measured. (d) The unknown volume of blood (x) in patient body is then
determined as- y S1 = (x + y) S2 but, y << x i.e x + y = x
y S1 = x S2 x = y cm3
* Normal adult human being may have about 5 to 6 litres of blood.
10. (D) Carbon dating: - (W. F. Libby (1960) first developed this technique.)
The process of determining the age of historic and archaeological
organic samples by comparing the ratio of 14
C to 12
C is called 14
C dating or
carbon dating.
The isotope 14
C is radioactive. The 14
C atom is produced in upper atmosphere
by the bombardment of neutron on Nitrogen atom.
N + n C + H
The atmospheric carbon dioxide a mixture of 14
CO2 and 12
CO2 present in
a fixed ratio. Plants absorb CO2 from the atmosphere and prepare cellulose
(wood) by photosynthesis. As long as the plant is alive the ratio of 14
C to 12
C
atoms in the wood is the same as in the atmosphere.
When the tree is cut, this cycle stops and the ratio 14
C to 12
C begins to
decrease because the 14
C atoms are constantly disintegrating. The concentration of
14
C can be measured by counting its radioactivity.
If N0 concentration of 14
C in fresh (living) tree
Nt concentration of 14
C at particular time t (after cutting),
The age of the historical object (i.e. time, t), can be determined by formula,
λ =
.
log where, λ = 0.693 / /
here, / Half life period of radioactive carbon (14
C). = 5730 years.
Preparation of transuranic element:-
When Uranium is bombarded with neutrons of certain velocity, one neutron is
captured and gives new isotopes of uranium.
U + n U + γ H
This isotope of Uranium is much more radioactive than natural Uranium. It
emits a beta particle and gives Neptunium having atomic number 93 which is
does not occur in nature.
U Np + e
Neptunium is also radioactive and emits a beta particle and gives Plutonium
having atomic number 94.
Np Pu + e
Plutonium further undergoes beta-ray change and in this way, by
appropriate nuclear reaction new elements are formed. (Americium-95,
Curium-96, Berkelium-97.....etc)