Thursday, November 22, 2018
Friday, November 9, 2018
IR FREQUENCY TABLE
https://www.chegg.com/homework-help/questions-and-answers/please-fill-table-three-products-refer-ir-absorption-frequency-table-attached-q19412976
Chemistry Lab Rules and Regulations
Chemistry Lab
Rules and Regulations
1.
Always follow
the lecturers directions and only do lab
work when a lecturer is present. you must get permission from the lecturerl
before beginning any activity OR using
any tools in the lab.d
2.
Do only the
experiments assigned or approved by the Lecturer.Unauthorised experiments are
prohibited.
3. Before you start an experiment, make sure you are
fully aware of the hazards of the materials you'll be using.
4. When refluxing, distilling, or transferring
volatile liquids, always exercise extreme caution.
5. Always pour chemicals from large containers to
smaller ones.
6. Never pour chemicals that have been used back into
the stock container.
7.
Do not mix
any two chemicals without permission of lab supervisor.
8. Cell phone stick strictly prohibited in the lab.
9. Chemicals should never be mixed, measured, or
heated in front of your face.
10.
Water should
not be poured into concentrated acid. Instead, pour acid slowly into water
while stirring constantly. In many cases, mixing acid with water is
exothermic.
11.
Cell phones strictly
probhited in Lab
12.
Submit lab observation
immediately after experiment is
over.
13.
Get signatureof lecturer on
record immediately after observation book signed.
Chemistry laboratory safety rules
Chemistry
laboratory safety rules
Ø Read the Chemical Safety
Information (MSDS)
Ø
Don't Taste or Smell Chemicals
Ø
Don't Eat or Drink in Lab
Ø Do not work
alone in the lab
Ø Wear apron, safety glasses and gloves when you are working in
the lab.when we use glassware be sure how to check it for chips and cracks
Ø
Take Data During Lab
Ø When you use
glassware, be sure to check it for chips and cracks.
Ø Follow the proper
procedures for disposing lab waste.
Ø In the event of a chemical
splashing into your eye(s) or on your skin, immediately flush the affected
area(s) with running water for at least 20 minutes.
Ø Always
keep your work area(s) tidy and clean.
Ø After
handling Chemicals wash your hands with soap.
Chemistry of Tea
Chemical
Compounds in Tea
·
Polyphenols.
·
Amino
Acids.
·
Enzymes.
Polyphenol oxidase and peroxidase are the most important enzymes in tea leaves.
...
·
Pigments.
Plant pigments are responsible for absorbing light for photosynthesis. ...
·
Carbohydrates.
...
·
Methylxanthines.
·
Minerals.
...
·
Volatiles.
There
are an estimated 30,000 polyphenolic compounds in tea4, flavonoids
are arguably the most important group of polyphenols in tea and are the source
of the many health claims surrounding tea, and specifically tea
antioxidants. Within the flavonoid group, flavanols (also known as
flavan-3-ols) are the most prevalent. Flavanols are also referred to as
tannins, and during oxidation are converted to theaflavins and thearubigins—the
compounds responsible for the dark color and robust flavors notably present in
black teas.
The
major flavanols in tea are: catechin (C), epicatechin (EC), epicatechin gallate
(ECG), gallocatechin (GC), epigallocatechin (EGC), and epigallocatechin gallate
(EGCG). EGCG is the most active of these catechins and is often the subject of
studies regarding tea antioxidants. Tea flavanols are sometimes collectively
referred to as catechins.
Besides flavanols, tea flavonoids also include flavonols, flavones,
isoflavones, and anthocyanins; all of which contribute to the color of a
tea’s infusion and its taste.
Amino Acids
Tea leaves contain many amino
acids, the most abundant of which is theanine. In the tea field, sunlight
converts amino acids to polyphenols, and as such; shade grown tea contains more
amino acids than tea grown in direct sunlight. Some tea bushes are even
deliberately shaded for several weeks before harvest to enhance the tea’s amino
acid content. Theanine, more specifically L-Theanine is responsible for promoting alpha brain wave activity
which promotes relaxation.
Methylxanthines
Methylxanthines in tea include the
stimulant caffeine and two similar compounds: theobromine and theophylline.
Methylxanthines also contribute to a bitter taste in the tea infusion. Caffeine is a central nervous system stimulant of the methylxanthine
class. It is the world's most widely consumed psychoactive drug. Unlike many
other psychoactive substances, it is legal and unregulated in nearly all parts
of world.
Minerals
28 mineral elements have been found in the tea flush5. Compared to other plants, tea has a higher than average amount of: fluorine, manganese, arsenic, nickel, selenium, iodine, aluminum, and potassium5
28 mineral elements have been found in the tea flush5. Compared to other plants, tea has a higher than average amount of: fluorine, manganese, arsenic, nickel, selenium, iodine, aluminum, and potassium5
Enzymes
Polyphenol oxidase and peroxidase are the most important enzymes in tea leaves
Polyphenol oxidase and peroxidase are the most important enzymes in tea leaves
pigments :There
are two major groups of pigments in fresh tea leaves: chlorophylls and
carotenoids.
Chemistry of Milk
Milk = water(85-
90 %) +
proteins + fats + lactose + minerals
Milk protein: Casein
(80%) and Whey protein (20%). Casein miscelle is a chain of amino acids
generally bounded by minerals and fats. Casein is a phoshoprotein and exist as
a calicium salt, calicium caseinate. As a food source, casein supplies amino
acids, carbohydrates, and the two inorganic elements calcium and phosphorus.
Lactoses molecular formula for lactose is
C12H22O11. Lactose is formed from galactose and glucose units. Lactose is the
main carbohydrate in milk. Lactose is responsible for drawing water into the
milk as it is being formed in the mammary glands of mammals.
Milk fat is a mixture of different fatty acids and glycerol.Milk fat is a mixture of different fatty acids and glycerol.Albumins are globular proteins that are
soluble in water and in dilute salt solutions. They are, however, denatured and
coagulated by heat. The second most abundant protein types in milk are the
lactalbumins. Once the caseins have been removed, and the solution has been
made acidic, the lactalbumins can be isolated by heating the mixture to
precipitate them. The typical albumin has a molecular weight of about 41,000. A
third type of protein in milk is the lactoglobulins. They are present in
smaller amounts than the albumins and generally denature and precipitate under
the same conditions as the albumin.
Caseinates:
A beneficial property of the casein molecule is its ability to form a gel or
clot in the stomach, which makes it very efficient in nutrient supply. The clot
is able to provide a sustained slow release of amino acids into the blood
stream, sometimes lasting for several hours. Casein is the reason for milk
being white opaque in visible spectrum.
Casein
proteins are composed of the following amino acids:
- 20.2% Glutamic
Acid
- 10.2% Proline
- 8.3% Leucine*
- 7.4% Lysine*
- 6.5% Valine*
- 6.4% Aspartic
Acid
- 5.7% Serine
- 5.7% Tyrosine
- 5.5% Isoleucine*
- 4.5% Phenylalanine*
- 4.4% Threonine*
- 3.7% Arginine
- 2.8% Histidine
- 2.7% Alanine
- 2.5% Methionine*
- 2.4% Glycine
- 1.1% Tryptophan*
- 0.3% Cystine
Women Noble Prizes in Chemistry
Women Noble Prizes in
Chemistry
Ø Frances H Arnold:
Awarded the Nobel Prize jointly
with
George Smith, Greg Winter
in Chemistry for
producing new enzymes and antibodies, including
Frances H Arnold.
Ø Marie
Curie (1911): Awarded the Nobel Prize “in recognition of
her services to the advancement of chemistry by the discovery of the elements
radium and polonium, by the isolation of radium and the study of the nature and
compounds of this remarkable element.”
Ø Irène
Joliot-Curie (1935): Awarded the Nobel Prize jointly with her
husband, Frédéric Joliot, “in recognition of their synthesis of new
radioactive elements.”
Ø Dorothy
Crowfoot Hodgkin (1964): Awarded the Nobel
Prize ”for her determinations by X-ray techniques of the structures of
important biochemical substances.”
Ø Ada
E. Yonath (2009): Jointly with Venkatraman Ramakrishnan
and Thomas A. Steitz “for studies of the structure and function of the
ribosome.”
Thursday, November 8, 2018
Nobel prize in Chemistry
Nobel Prizes in
Chemistry
The Nobel Prize in
Chemistry has been awarded 110 times to 181 Nobel Laureates between 1901 and
2018. Frederick Sanger is the only Nobel Laureate who has been awarded the
Nobel Prize in Chemistry twice, in 1958 and 1980. This means that a total of
180 individuals have received the Nobel Prize in Chemistry.
Frances H. Arnold “for the
directed evolution of enzymes”, George P. Smith and Sir Gregory P. Winter “for the phage
display of peptides and antibodies”
Jacques Dubochet, Joachim Frank and Richard Henderson “for developing
cryo-electron microscopy for the high-resolution structure determination of
biomolecules in solution”
Jean-Pierre Sauvage, Sir J. Fraser Stoddart and Bernard L.
Feringa ”for
the design and synthesis of molecular machines”
Eric Betzig, Stefan W. Hell and William E. Moerner “for the
development of super-resolved fluorescence microscopy”
Martin Karplus, Michael Levitt and Arieh Warshel “for the
development of multiscale models for complex chemical systems”
Dan Shechtman “for the
discovery of quasicrystals”
Richard F. Heck, Ei-ichi Negishi and Akira Suzuki “for
palladium-catalyzed cross couplings in organic synthesis”
Venkatraman
Ramakrishnan, Thomas A. Steitz and Ada E. Yonath “for studies of
the structure and function of the ribosome”
Osamu Shimomura, Martin Chalfie and Roger Y. Tsien “for the
discovery and development of the green fluorescent protein, GFP”
Gerhard Ertl ”for his studies of
chemical processes on solid surfaces”
Roger D. Kornberg ”for his studies of
the molecular basis of eukaryotic transcription”
Yves Chauvin, Robert H. Grubbs and Richard R.
Schrock ”for
the development of the metathesis method in organic synthesis”
Aaron Ciechanover, Avram Hershko and Irwin Rose ”for the discovery of
ubiquitin-mediated protein degradation”
“for
discoveries concerning channels in cell membranes”, Peter Agre ”for the discovery of
water channels”, and Roderick MacKinnon ”for structural
and mechanistic studies of ion channels”
“for
the development of methods for identification and structure analyses of
biological macromolecules”
John B. Fenn and Koichi Tanaka ”for their
development of soft desorption ionisation methods for mass spectrometric
analyses of biological macromolecules”.
Kurt Wüthrich ”for his development
of nuclear magnetic resonance spectroscopy for determining the
three-dimensional structure of biological macromolecules in solution”
K. Barry Sharpless ”for his work
on chirally catalysed oxidation reactions”
Alan J. Heeger, Alan G. MacDiarmid and Hideki Shirakawa ”for the
discovery and development of conductive polymers”
Ahmed H. Zewail ”for his studies of
the transition states of chemical reactions using femtosecond spectroscopy”
Walter Kohn ”for his
development of the density-functional theory”
John A. Pople ”for his development
of computational methods in quantum chemistry”
Paul D. Boyer and John E. Walker ”for their
elucidation of the enzymatic mechanism underlying the synthesis of adenosine
triphosphate (ATP)”
Jens C. Skou ”for the first
discovery of an ion-transporting enzyme, Na+, K+ -ATPase”
Paul J. Crutzen, Mario J. Molina and F. Sherwood Rowland “for their work
in atmospheric chemistry, particularly concerning the formation and
decomposition of ozone”
George A. Olah “for his
contribution to carbocation chemistry”
“for
contributions to the developments of methods within DNA-based chemistry”
Kary B. Mullis ”for his
invention of the polymerase chain reaction (PCR) method”
Michael Smith ”for his
fundamental contributions to the establishment of oligonucleotide-based,
site-directed mutagenesis and its development for protein studies”
Rudolph A. Marcus ”for his
contributions to the theory of electron transfer reactions in chemical systems”
Richard R. Ernst ”for his
contributions to the development of the methodology of high resolution nuclear
magnetic resonance (NMR) spectroscopy”
Elias James Corey ”for his
development of the theory and methodology of organic synthesis”
Johann Deisenhofer, Robert Huber and Hartmut Michel ”for the
determination of the three-dimensional structure of a photosynthetic reaction
centre”
Donald J. Cram, Jean-Marie Lehn and Charles J. Pedersen ”for their
development and use of molecules with structure-specific interactions of high
selectivity”
Dudley R. Herschbach, Yuan T. Lee and John C. Polanyi ”for their
contributions concerning the dynamics of chemical elementary processes”
Herbert A. Hauptman and Jerome Karle “for their
outstanding achievements in the development of direct methods for the
determination of crystal structures”
Robert Bruce Merrifield “for his
development of methodology for chemical synthesis on a solid matrix”
Henry Taube “for his work
on the mechanisms of electron transfer reactions, especially in metal
complexes”
Aaron Klug “for his
development of crystallographic electron microscopy and his structural
elucidation of biologically important nucleic acid-protein complexes”
Kenichi Fukui and Roald Hoffmann “for their
theories, developed independently, concerning the course of chemical reactions”
Paul Berg ”for his
fundamental studies of the biochemistry of nucleic acids, with particular
regard to recombinant-DNA”
Walter Gilbert and Frederick Sanger “for their
contributions concerning the determination of base sequences in nucleic acids”
Herbert C. Brown and Georg Wittig “for their
development of the use of boron- and phosphorus-containing compounds,
respectively, into important reagents in organic synthesis”
Peter D. Mitchell “for his
contribution to the understanding of biological energy transfer through the
formulation of the chemiosmotic theory”
Ilya Prigogine “for his
contributions to non-equilibrium thermodynamics, particularly the theory of
dissipative structures”
William N. Lipscomb “for his
studies on the structure of boranes illuminating problems of chemical bonding”
John Warcup Cornforth “for his work
on the stereochemistry of enzyme-catalyzed reactions”
Vladimir Prelog ”for his research
into the stereochemistry of organic molecules and reactions”
Paul J. Flory ”for his
fundamental achievements, both theoretical and experimental, in the physical
chemistry of the macromolecules”
Ernst Otto Fischer and Geoffrey Wilkinson “for their
pioneering work, performed independently, on the chemistry of the
organometallic, so called sandwich compounds”
Christian B. Anfinsen “for his work
on ribonuclease, especially concerning the connection between the amino acid
sequence and the biologically active conformation”
Stanford Moore and William H. Stein “for their
contribution to the understanding of the connection between chemical structure
and catalytic activity of the active centre of the ribonuclease molecule”
Gerhard Herzberg “for his
contributions to the knowledge of electronic structure and geometry of
molecules, particularly free radicals”
Luis F. Leloir ”for his discovery of
sugar nucleotides and their role in the biosynthesis of carbohydrates”
Derek H. R. Barton and Odd Hassel “for their
contributions to the development of the concept of conformation and its
application in chemistry”
Lars Onsager “for the
discovery of the reciprocal relations bearing his name, which are fundamental
for the thermodynamics of irreversible processes”
Manfred Eigen, Ronald George Wreyford
Norrish and George Porter ”for their studies of
extremely fast chemical reactions, effected by disturbing the equilibrium by
means of very short pulses of energy”
Robert S. Mulliken “for his
fundamental work concerning chemical bonds and the electronic structure of
molecules by the molecular orbital method”
Robert Burns Woodward “for his
outstanding achievements in the art of organic synthesis”
Dorothy Crowfoot
Hodgkin ”for
her determinations by X-ray techniques of the structures of important
biochemical substances”
Karl Ziegler and Giulio Natta “for their
discoveries in the field of the chemistry and technology of high polymers”
Max Ferdinand Perutz and John Cowdery Kendrew “for their
studies of the structures of globular proteins”
Melvin Calvin “for his
research on the carbon dioxide assimilation in plants”
Willard Frank Libby “for his method
to use carbon-14 for age determination in archaeology, geology, geophysics, and
other branches of science”
Jaroslav Heyrovsky “for his
discovery and development of the polarographic methods of analysis”
Frederick Sanger “for his work
on the structure of proteins, especially that of insulin”
Lord (Alexander R.)
Todd “for
his work on nucleotides and nucleotide co-enzymes”
Sir Cyril Norman
Hinshelwood and Nikolay Nikolaevich
Semenov ”for
their researches into the mechanism of chemical reactions”
Vincent du
Vigneaud ”for
his work on biochemically important sulphur compounds, especially for the first
synthesis of a polypeptide hormone”
Linus Carl Pauling ”for his
research into the nature of the chemical bond and its application to the
elucidation of the structure of complex substances”
Hermann Staudinger “for his
discoveries in the field of macromolecular chemistry”
Archer John Porter
Martin and Richard Laurence
Millington Synge “for
their invention of partition chromatography”
Edwin Mattison McMillan and Glenn Theodore Seaborg “for their discoveries
in the chemistry of the transuranium elements”
William Francis Giauque “for his
contributions in the field of chemical thermodynamics, particularly concerning
the behaviour of substances at extremely low temperatures”
Arne Wilhelm Kaurin
Tiselius “for
his research on electrophoresis and adsorption analysis, especially for his
discoveries concerning the complex nature of the serum proteins”
Sir Robert
Robinson ”for
his investigations on plant products of biological importance, especially the
alkaloids”
James Batcheller Sumner “for his
discovery that enzymes can be crystallized”
John Howard Northrop and Wendell Meredith
Stanley ”for
their preparation of enzymes and virus proteins in a pure form”
Artturi Ilmari Virtanen “for his
research and inventions in agricultural and nutrition chemistry, especially for
his fodder preservation method”
Otto Hahn “for his
discovery of the fission of heavy nuclei”
George de Hevesy “for his work
on the use of isotopes as tracers in the study of chemical processes”
No
Nobel Prize was awarded this year. The prize money was with 1/3 allocated to
the Main Fund and with 2/3 to the Special Fund of this prize section.
No
Nobel Prize was awarded this year. The prize money was with 1/3 allocated to
the Main Fund and with 2/3 to the Special Fund of this prize section.
No
Nobel Prize was awarded this year. The prize money was with 1/3 allocated to
the Main Fund and with 2/3 to the Special Fund of this prize section.
Adolf Friedrich Johann
Butenandt “for
his work on sex hormones”
Leopold Ruzicka “for his work
on polymethylenes and higher terpenes”
Richard Kuhn ”for his work
on carotenoids and vitamins”
Walter Norman Haworth “for his
investigations on carbohydrates and vitamin C”
Paul Karrer “for his investigations
on carotenoids, flavins and vitamins A and B2”
Petrus (Peter) Josephus
Wilhelmus Debye “for
his contributions to our knowledge of molecular structure through his
investigations on dipole moments and on the diffraction of X-rays and electrons
in gases”
Frédéric Joliot and Irène Joliot-Curie “in recognition
of their synthesis of new radioactive elements”
Harold Clayton Urey “for his discovery
of heavy hydrogen”
No
Nobel Prize was awarded this year. The prize money was with 1/3 allocated to
the Main Fund and with 2/3 to the Special Fund of this prize section.
Irving Langmuir “for his
discoveries and investigations in surface chemistry”
Carl Bosch and Friedrich Bergius ”in recognition of
their contributions to the invention and development of chemical high pressure
methods”
Hans Fischer “for his
researches into the constitution of haemin and chlorophyll and especially for
his synthesis of haemin”
Arthur Harden and Hans Karl August Simon
von Euler-Chelpin “for
their investigations on the fermentation of sugar and fermentative enzymes”
Adolf Otto Reinhold
Windaus ”for
the services rendered through his research into the constitution of the sterols
and their connection with the vitamins”
Heinrich Otto Wieland “for his
investigations of the constitution of the bile acids and related substances”
The (Theodor)
Svedberg ”for
his work on disperse systems”
Richard Adolf Zsigmondy “for his
demonstration of the heterogenous nature of colloid solutions and for the
methods he used, which have since become fundamental in modern colloid
chemistry”
No
Nobel Prize was awarded this year. The prize money was allocated to the Special
Fund of this prize section.
Fritz Pregl “for his
invention of the method of micro-analysis of organic substances”
Francis William Aston “for his
discovery, by means of his mass spectrograph, of isotopes, in a large number of
non-radioactive elements, and for his enunciation of the whole-number rule”
Frederick Soddy ”for his
contributions to our knowledge of the chemistry of radioactive substances, and
his investigations into the origin and nature of isotopes”
Walther Hermann Nernst “in recognition
of his work in thermochemistry”
No
Nobel Prize was awarded this year. The prize money was allocated to the Special
Fund of this prize section.
Fritz Haber “for the
synthesis of ammonia from its elements”
No
Nobel Prize was awarded this year. The prize money was allocated to the Special
Fund of this prize section.
No
Nobel Prize was awarded this year. The prize money was allocated to the Special
Fund of this prize section.
Richard Martin
Willstätter “for
his researches on plant pigments, especially chlorophyll”
Theodore William
Richards ”in
recognition of his accurate determinations of the atomic weight of a large
number of chemical elements”
Alfred Werner “in recognition
of his work on the linkage of atoms in molecules by which he has thrown new
light on earlier investigations and opened up new fields of research especially
in inorganic chemistry”
Victor Grignard “for the
discovery of the so-called Grignard reagent, which in recent years has greatly
advanced the progress of organic chemistry”
Paul Sabatier “for his method
of hydrogenating organic compounds in the presence of finely disintegrated
metals whereby the progress of organic chemistry has been greatly advanced in
recent years”
Marie Curie, née
Sklodowska “in
recognition of her services to the advancement of chemistry by the discovery of
the elements radium and polonium, by the isolation of radium and the study of
the nature and compounds of this remarkable element”
Otto Wallach “in recognition
of his services to organic chemistry and the chemical industry by his pioneer
work in the field of alicyclic compounds”
Wilhelm Ostwald “in recognition
of his work on catalysis and for his investigations into the fundamental
principles governing chemical equilibria and rates of reaction”
Ernest Rutherford “for his
investigations into the disintegration of the elements, and the chemistry of
radioactive substances”
Eduard Buchner “for his biochemical
researches and his discovery of cell-free fermentation”
Henri Moissan ”in recognition of
the great services rendered by him in his investigation and isolation of the
element fluorine, and for the adoption in the service of science of the
electric furnace called after him”
Johann Friedrich
Wilhelm Adolf von Baeyer “in recognition of his services in the advancement of
organic chemistry and the chemical industry, through his work on organic dyes
and hydroaromatic compounds”
Sir William Ramsay ”in recognition
of his services in the discovery of the inert gaseous elements in air, and his
determination of their place in the periodic system”
Svante August Arrhenius “in recognition
of the extraordinary services he has rendered to the dvancement of chemistry by
his electrolytic theory of dissociation”
Hermann Emil Fischer ”in recognition
of the extraordinary services he has rendered by his work on sugar and purine
syntheses”
Jacobus Henricus van ‘t
Hoff “in
recognition of the extraordinary services he has rendered by the discovery of
the laws of chemical dynamics and osmotic pressure in solutions”
To
cite this section
https://www.nobelprize.org/prizes/lists/all-nobel-prizes-in-chemistry/
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https://www.chegg.com/homework-help/questions-and-answers/please-fill-table-three-products-refer-ir-absorption-frequency-table-attached-q19... -
Nobel Prizes in Chemistry The Nobel Prize in Chemistry has been awarded 110 times to 181 Nobel Laureates between 1901 and 2018. Freder...
-
Women Noble Prizes in Chemistry Ø Frances H Arnold: Awarded the Nobel Prize jointly with George Smith , Greg Winter in Chem...