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Earth Chemistry


As we celebrate Earth Day, and as in recent times, emphasis has been given to environmental awareness or the value of “green.” This year, let’s pay attention to all the other colors of Earth as well – the colors we see through chemistry.

Chemistry of Carbon and Its Compounds


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Carbon: Introduction


Atomic Number: 6 

Electronic configuration: 2, 4 

Valence electrons: 4

Property: Non-metal

Abundance: Carbon is the 4th most abundant substance in universe and 15th most abundant substance in the earth’s crust.

Compounds having carbon atoms among the components are known as carbon compounds. Previously, carbon compounds could only be obtained from a living source; hence they are also known as organic compounds.

Bonding In Carbon: Covalent Bond

Bond formed by sharing of electrons is called covalent bond. Two of more atoms share electrons to make their configuration stable. In this type of bond, all the atoms have similar rights over shared electrons. Compounds which are formed because of covalent bond are called COVALNET COMPOUNDS.

Covalent bonds are of three types: Single, double and triple covalent bond.

Single Covalent Bond: Single covalent bond is formed because of sharing of two electrons, one from each of the two atoms.

Formation of hydrogen molecule (H2)

Atomic Number of H = 1

Electronic configuration of H = 1

Valence electron of H = 1

Hydrogen forms a duet, to obtain stable configuration. This configuration is similar to helium (a noble gas).

Since, hydrogen has one electron in its valence shell, so it requires one more electron to form a duet. So, in the formation of hydrogen molecule; one electron from each of the hydrogen atoms is shared.





Formation of hydrogen chloride (HCl):

Valence electron of hydrogen = 1

Atomic number of chlorine = 17

Electronic configuration of chlorine: 2, 8, 7

Electrons in outermost orbit = 7

Valence electron = 7





Formation of chlorine molecule (Cl2):

Valence electron of chlorine = 7





Formation of water (H2O)

Valence electron of hydrogen = 1

Atomic number of oxygen = 8

Electronic configuration of oxygen = 2, 6

Valence electron = 6

Oxygen in water molecule completes stable configuration by the sharing one electron from each of the two hydrogen atoms.



Formation of Methane (CH4)

Valence electron of carbon = 4

Valence electron of hydrogen = 1



Formation of Ethane (C2H6):





Double covalent bond: Double bond is formed by sharing of four electrons, two from each of the two atoms.

Formation of oxygen molecule (O2):

Valence electron of oxygen = 2



In the formation of oxygen molecule, two electrons are shared by each of the two oxygen atoms to complete their stable configuration.

In oxygen, the total number of shared electrons is four, two from each of the oxygen atoms. So a double covalent bond is formed.

Formation of Carbon dioxide (CO2):

Valence electron of carbon = 4

Valence electron of oxygen = 6

In carbon dioxide two double covalent bonds are formed.



Formation of Ethylene (C2H4):

Valence electron of carbon = 4

Valence electron of hydrogen = 1



Triple Covalent Bond: Triple covalent bond is formed because of the sharing of six electrons, three from each of the two atoms.



Formation of Nitrogen (N2):

Atomic number of nitrogen = 7

Electronic configuration of nitrogen = 2, 5

Valence electron = 5



In the formation of nitrogen, three electrons are shared by each of the nitrogen atoms. Thus one triple bond is formed because of the sharing of total six electrons.



Formation of Acetylene (C2H2):



Properties of Covalent Bond:

  • Intermolecular force is smaller.

  • Covalent bonds are weaker than ionic bond. As a result, covalent compounds have low melting and boiling points.

  • Covalent compounds are poor conductor of electricity as no charged particles are formed in covalent bond.

  • Since, carbon compounds are formed by the formation of covalent bond, so carbon compounds generally have low melting and boiling points and are poor conductor of electricity.

5.1 Biochemistry, sometimes called biological chemistry, is the study of chemical processes within and relating to living organisms.[1]By controlling information flow through biochemical signaling and the flow of chemical energy through metabolism, biochemical processes give rise to the complexity of life. Over the last decades of the 20th century, biochemistry has become so successful at explaining living processes that now almost all areas of the life sciences from botany to medicine to genetics are engaged in biochemical research.[2] Today, the main focus of pure biochemistry is on understanding how biological molecules give rise to the processes that occur within living cells,[3] which in turn relates greatly to the study and understanding of tissuesorgans, and whole organisms[4]—that is, all of biology.

Biochemistry is closely related to molecular biology, the study of the molecular mechanisms by which genetic information encoded inDNA is able to result in the processes of life.[5] Depending on the exact definition of the terms used, molecular biology can be thought of as a branch of biochemistry, or biochemistry as a tool with which to investigate and study molecular biology.

Much of biochemistry deals with the structures, functions and interactions of biological macromolecules, such as proteinsnucleic acidscarbohydrates and lipids, which provide the structure of cells and perform many of the functions associated with life.[6] The chemistry of the cell also depends on the reactions of smaller molecules and ions. These can be inorganic, for example water andmetal ions, or organic, for example the amino acids, which are used to synthesize proteins.[7] The mechanisms by which cells harness energy from their environment via chemical reactions are known as metabolism. The findings of biochemistry are applied primarily in medicinenutrition, and agriculture. In medicine, biochemists investigate the causes and cures of diseases.[8] In nutrition, they study how to maintain health and study the effects of nutritional deficiencies.[9] In agriculture, biochemists investigate soil andfertilizers, and try to discover ways to improve crop cultivation, crop storage and pest control.

Biochemistry is the branch of science that explores the chemical processes within and related to living organisms. It is a laboratory based science that brings together biology and chemistry. By using chemical knowledge and techniques, biochemists can understand and solve biological problems.


Biochemistry focuses on processes happening at a molecular level. It focuses on what’s happening inside our cells, studying components like proteins, lipids and organelles. It also looks at how cells communicate with each other, for example during growth or fighting illness. Biochemists need to understand how the structure of a molecule relates to its function, allowing them to predict how molecules will interact.

Biochemistry covers a range of scientific disciplines, including genetics, microbiology, forensics, plant science and medicine. Because of its breadth, biochemistry is very important and advances in this field of science over the past 100 years have been staggering. It’s a very exciting time to be part of this fascinating area of study.


 

What do biochemists do?


  • Provide new ideas and experiments to understand how life works

  • Support our understanding of health and disease

  • Contribute innovative information to the technology revolution

  • Work alongside chemists, physicists, healthcare professionals, policy makers, engineers and many more professionals

Biochemists work in many places, including:

  • Hospitals

  • Universities

  • Agriculture

  • Food institutes

  • Education

  • Cosmetics

  • Forensic crime research

  • Drug discovery and development

  Biochemists have many transferable skills, including:

  • Analytical

  • Communication

  • Research

  • Problem solving

  • Numerical

  • Written

  • Observational

  • Planning

 The life science community is a fast-paced, interactive network with global career opportunities at all levels. The Government recognizes the potential that developments in biochemistry and the life sciences have for contributing to national prosperity and for improving the quality of life of the population. Funding for research in these areas has been increasing dramatically in most countries, and the biotechnology industry is expanding rapidly.

At its broadest definition, biochemistry can be seen as a study of the components and composition of living things and how they come together to become life, and the history of biochemistry may therefore go back as far as the ancient Greeks.[10] However, biochemistry as a specific scientific discipline has its beginning some time in the 19th century, or a little earlier, depending on which aspect of biochemistry one is being focused on. Some argued that the beginning of biochemistry may have been the discovery of the first enzymediastase (today called amylase), in 1833 byAnselme Payen,[11] while others considered Eduard Buchner's first demonstration of a complex biochemical process alcoholic fermentation in cell-free extracts in 1897 to be the birth of biochemistry.[12][13] Some might also point as its beginning to the influential 1842 work by Justus von Liebig,Animal chemistry, or, Organic chemistry in its applications to physiology and pathology, which presented a chemical theory of metabolism,[10] or even earlier to the 18th century studies on fermentation and respiration by Antoine Lavoisier.[14][15] Many other pioneers in the field who helped to uncover the layers of complexity of biochemistry have been proclaimed founders of modern biochemistry, for example Emil Fischer for his work on the chemistry of proteins,[16] and F. Gowland Hopkins on enzymes and the dynamic nature of biochemistry.[17]

The term "biochemistry" itself is derived from a combination of biology and chemistry. In 1877, Felix Hoppe-Seyler used the term (biochemie in German) as a synonym for physiological chemistry in the foreword to the first issue of Zeitschrift für Physiologische Chemie (Journal of Physiological Chemistry) where he argued for the setting up of institutes dedicated to this field of study.[18][19] The German chemist Carl Neuberghowever is often cited to have been coined the word in 1903,[20][21][22] while some credited it to Franz Hofmeister.[23]

DNA structure (1D65​)[24]

It was once generally believed that life and its materials had some essential property or substance (often referred to as the "vital principle") distinct from any found in non-living matter, and it was thought that only living beings could produce the molecules of life.[25] Then, in 1828, Friedrich Wöhler published a paper on the synthesis of urea, proving that organic compounds can be created artificially.[26] Since then, biochemistry has advanced, especially since the mid-20th century, with the development of new techniques such as chromatographyX-ray diffractiondual polarisation interferometryNMR spectroscopyradioisotopic labelingelectron microscopy, and molecular dynamics simulations. These techniques allowed for the discovery and detailed analysis of many molecules and metabolic pathways of the cell, such as glycolysis and theKrebs cycle (citric acid cycle).

Another significant historic event in biochemistry is the discovery of the gene and its role in the transfer of information in the cell. This part of biochemistry is often called molecular biology.[27] In the 1950s, James D. WatsonFrancis CrickRosalind Franklin, and Maurice Wilkins were instrumental in solving DNA structure and suggesting its relationship with genetic transfer of information.[28] In 1958, George Beadle and Edward Tatum received the Nobel Prize for work in fungi showing that one gene produces one enzyme.[29] In 1988, Colin Pitchfork was the first person convicted of murder with DNA evidence, which led to growth of forensic science.[30] More recently, Andrew Z. Fire and Craig C. Mello received the2006 Nobel Prize for discovering the role of RNA interference (RNAi), in the silencing of gene expression.[31]



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