Saturday 29 September 2012

Raman Spectroscopy

It is the shift in wavelength of the inelastically scattered radiation that provides the chemical and structural information. Raman shifted photons can be of either higher or lower energy, depending upon the vibrational state of the molecule under study. For more click here.
 
Credit: National University of Singapore

Credit: http://www.andor.com/learning-academy

Thursday 27 September 2012

Symmetry and Group Theory

Group Theory is a mathematical method by which aspects of a molecules symmetry can be determined. 

The symmetry of a molecule reveals information about its properties (i.e., structure, spectra, polarity, chirality, etc…)
Credit: http://chemwiki.ucdavis.edu


Courtesy: http://chemistry.rutgers.edu

Wednesday 26 September 2012

Anti-cancer Drug

Cisplatin is a chemotherapy drug which is used to treat cancers including: sarcoma, small cell lung cancer, germ cell tumors, lymphoma, and ovarian cancer. For more click here.


Courtesy: http://www.cisplatin.org/

Monday 24 September 2012

Polymers

Prior to the early 1920's, chemists doubted the existence of molecules having molecular weights greater than a few thousand. This limiting view was challenged by Hermann Staudinger, a German chemist with experience in studying natural compounds such as rubber and cellulose. In contrast to the prevailing rationalization of these substances as aggregates of small molecules, Staudinger proposed they were made up of macromolecules composed of 10,000 or more atoms. Read more here.


Courtesy: William Reusch, 

Saturday 22 September 2012

Amino Acid

In 1953, Harold Urey and Stanley Miller carried out an amazing experiment in which they produced "molecules of life" from a mixture of gases that they proposed existed in a primordial earth. The experiments simulated what would happen when lightning strikes provided energy for chemical reactions in the atmosphere and suggested a hypothesis for how life might have developed on our planet. Amino acids were the vital molecules that formed in this experiment and supported this hypothesis for the origin of life. 

Friday 21 September 2012

The Common Ion Effect

The presence of a common ion suppresses the ionization of a weak acid or a weak base. The common ion effect is the shift in equilibrium caused by the addition of a compound having an ion in common with the dissolved substance.  For more click here.


Courtesy: Dr. Walter S. Hamilton, https://chemistry.twu.edu

Thursday 20 September 2012

Stereochemistry

Stereoisomerism is a more subtle kind of isomerism in which the isomers differ only in their spatial arrangement, not in their connectivity. Cis- and Trans-1,4-dimethylcyclohexane are a good example of a pair of stereoisomers. For more click here.

 CourtesyProfessor Nathan L. Bauld, http://research.cm.utexas.edu

Wednesday 19 September 2012

Heat and Energy

Energy is the ability to do work on matter. Heat or, thermal energy is the total energy associated with random atomic and molecular motions of a substance. Read more here.

 Courtesy: Ritter, Michael E., The Physical Environment: an Introduction to Physical Geography.

Tuesday 18 September 2012

Ions in solution

In Binary Ionic Compounds and Their Properties we point out that when an ionic compound dissolves in water, the positive and negative ions originally present in the crystal lattice persist in solution. Their ability to move nearly independently through the solution permits them to carry positive or negative electrical charges from one place to another. Hence the solution conducts an electrical current. For more click here.

Monday 17 September 2012

Nuclear Chemistry


An atom consists of an extremely small, positively charged nucleus surrounded by a cloud of negatively charged electrons. Although typically the nucleus is less than one ten-thousandth the size of the atom, the nucleus contains more than 99.9% of the mass of the atom! Nuclei consist of positively charged protons and electrically neutral neutrons held together by the so-called strong or nuclear force. Read more here.


Courtesy: http://www.lbl.gov/abc

Sunday 16 September 2012

Introduction: Ozone Layer Depletion

The distribution of ozone in the stratosphere is a function of altitude, latitude and season. It is determined by photochemical and transport processes. The ozone layer is located between 10 and 50 km above the Earth's surface and contains 90% of all stratospheric ozone. Under normal conditions, stratospheric ozone is formed by a photochemical reaction between oxygen molecules, oxygen atoms and solar radiation. Read more here.

Courtesy: http://esl.jrc.it

World Ozone Day - 16 September 2012

In 1998, in recognition of the Protocol's unique accomplishments, the General Assembly in its Resolution 49/114 named 16 September as the International day for the Preservation of the Ozone Layer. Since that time, the Parties have used this day to celebrate the signing of the Montreal Protocol, and the significant environmental and health benefits that this amazing treaty has yielded. 


The Montreal Protocol is celebrating its 25th Anniversary this year. 

Courtesy: http://ozone.unep.org

Saturday 15 September 2012

Introduction to Spectroscopy

Spectroscopy is the study of the interaction between matter and radiated energy. For more click here.

Courtesy: http://imagine.gsfc.nasa.gov/

Friday 14 September 2012

Alcohol, Chemistry and You

Acute and chronic alcohol consumption can have both subtle as well as dramatic effects on the brain and its functioning. For more click here.


 Courtesy: Dr. Bill Boggan, Kennesaw State University

Thursday 13 September 2012

Aspirin

Aspirin (acetylsalicylic acid, see Figure) was introduced as an analgesic (pain-relieving agent) in the late nineteenth century by chemists at Bayer, a German pharmaceutical company.

Lipids

The lipids are a large and diverse group of naturally occurring organic compounds that are related by their solubility in nonpolar organic solvents (e.g. ether, chloroform, acetone & benzene) and general insolubility in water. For more click here.


Courtesy: reusch, http://www2.chemistry.msu.edu

Wednesday 12 September 2012

Know Medicinal Plants - 2

Emblica officinalis:

Amla is one of the most celebrated herbs in the Indian traditional medicine system, Ayurveda. For more click here.

Courtesy: http://emblica-officinalis.101herbs.com/ 

Tuesday 11 September 2012

Water Chemistry

  1. Water is the most common substance known to man, as well as the most important. In vapor, liquid or solid form, water covers more than seventy percent of the Earth's surface, and is a major component of the atmosphere. Water is also an essential requirement for all forms of life. Most living things are largely made up of water. Human beings, for example, consist of about two-thirds water. For more click here.

  2. Courtesy: http://www.milanco.com 

  3. Another Link is here 


    Courtesy: http://www.biology.arizona.edu

Monday 10 September 2012

Chemical Kinetics - Basics

A reaction is of zero order when the rate of reaction is independent of the concentration of materials. The rate of reaction is a constant. When the limiting reactant is completely consumed, the reaction stops abruptly. For more click here
Arrhenius

Courtesy: Peter Keusch, University of Regensburg

Saturday 8 September 2012

All about Electrochemistry

The connection between chemistry and electricity is a very old one, going back to Alessandro Volta's discovery, in 1793, that electricity could be produced by placing two dissimilar metals on opposite sides of a moistened paper. For more click here.

Courtesy: Stephen Lower, Simon Fraser University

Friday 7 September 2012

Basic Photochemistry

Photochemistry is the underlying mechanism for all of photobiology. When a molecule absorbs a photon of light, its electronic structure changes, and it reacts differently with other molecules. For more click here.
Jablonski diagram

Courtesy: Emeritus Professor Kendric C. Smith, Stanford University School of Medicine

Thursday 6 September 2012

Carbohydrates

Carbohydrates are the most abundant class of organic compounds found in living organisms. They originate as products of photosynthesis, an endothermic reductive condensation of carbon dioxide requiring light energy and the pigment chlorophyll. For more click here.


Courtesyhttp://www2.chemistry.msu.edu/

Wednesday 5 September 2012

Teacher's Day

The best teacher is the one who suggests rather than dogmatizes, and inspires his listener with the wish to teach himself.

Tuesday 4 September 2012

Acids and Bases

You hear about acids all the time. Acid reflux disease causes some people to have to take acid reducing medication. The fact of the matter is that you hear the word "acid" all the time. Most of us, however, don't have any idea what an acid is. For more Click here.


Courtesy: http://misterguch.brinkster.net

Monday 3 September 2012

Introduction to Polymers

Polymers are a large class of materials consisting of many small molecules (called monomers) that can be linked together to form long chains, thus they are known as macromolecules. Read more here.
Addition polymerization steps

Courtesy: http://plc.cwru.edu

Sunday 2 September 2012

A SIMPLE VIEW OF ATOMIC STRUCTURE

What happens if a beam of each of these particles is passed between two electrically charged plates - one positive and one negative? For more details click here.

Courtesy: Jim Clark, http://www.chemguide.co.uk

Saturday 1 September 2012

Naming Organic Compounds

The increasingly large number of organic compounds identified with each passing day, together with the fact that many of these compounds are isomers of other compounds, requires that a systematic nomenclature system be developed. Just as each distinct compound has a unique molecular structure which can be designated by a structural formula, each compound must be given a characteristic and unique name. For more click here.
Courtesy: William Reusch, http://www.chemistry.msu.edu/
Message from Bhagavath Geetha
  • Do not get over excited over happiness and do not get over depressed over sorrow.
  • Do not get over bonded with anyone and anybody because it can lead to problems and sorrow.
  • Never think that my duty is the topmost or lowermost. Every duty is respectful. The responsibility undertaken or given as per the position is the noblest duty.
  • Elevate yourselves, family, society and nation and never denigrate yourselves, family, society and nation.
  • We are our own closest relatives and if not properly utilised we will become our closest enemies.
  • There are possibilities of success and failure in any endeavour. One cannot assure success always.
  • Death is inevitable for everyone in this world. In any endeavour at the maximum an individual may die.
  • People may say good and also they may say bad. Approach them with stabilised mind.
  • Take anything after scientifically, logically and rationally analysing them.
  • Perform your duty, responsibility and accept the privileges eligible for you.
  • First change ourselves and then try to change others.
  • We are all instruments /tools in the hands of the nature for performing the duty. So do not think that I am doing the duty. Think that I am an instrument to do the duty.
  • Results of action may not be sweet always. Accept what ever may be the result.
  • Follow the path of great scholars who guided the world. Listen their messages.
  • Results and rewards will come and go but stick to your duty with devotion, dedication and sincerity.