Posts Tagged ‘Chemistry’

In the night sky, the expanses of space between the stars of the Milky Way appear to be empty. In fact this space is occupied by a very thin gas that is mostly hydrogen and that has mere traces (less than 0.1% by number of atoms) of other elements such as oxygen, carbon, and nitrogen. The gas is also dusty; it contains grains of dust (particulate matter) that, like an interstellar fog, impede one’s view of the stars. This gas is not evenly spread in space, but is clumpy. Although on average there is approximately one hydrogen atom for every cubic centimeter of interstellar space, a clump may be one thousand or more times as dense as a comparable volume of average density. Since about 1970 astronomers have been finding that these denser regions contain a great variety of molecules; about 120 different molecular species have been identified in the interstellar medium. The study of these molecules in the Milky Way and in other galaxies is called astrochemistry.

Astronomers identify interstellar atoms and molecules via spectroscopy . For example, interstellar sodium atoms that happen to be in a line of sight going from a point on Earth’s surface toward a bright star absorb light emitted by that star at a wavelength that is characteristic of sodium atoms (about 589 nanometers; 2.3×10−5 inches). Most interstellar molecules are detected by spectroscopic analysis that measures absorption or emission at radio wavelengths rather than those corresponding to visual light. Astronomers use large radio telescopes to detect radiation emitted by interstellar molecules. These emissions arise because the molecules are set to rotating when they collide with each other. The molecules lose energy and slow down in their rotations by emitting radiation at wavelengths that are specific for them, such that each emission is a “signature” of one type of molecule. For example, the molecule carbon monoxide, CO, may emit at various radio wavelengths, including 2.6 millimeters (0.1 inches), 1.3 millimeters (0.05 inches),0.65 millimeters (0.03 inches), and 0.32 millimeters (0.01 inches). Interstellar gas is usually very cold (around 10 degrees above absolute zero), but even under these conditions the molecular collisions are energetic enough to keep the molecules rotating and, therefore, emitting radiation. About 120 types of molecules have been identified in the space between the stars in our galaxy.

Sometimes these interstellar molecules may be located in warmer regions. If the gas of which they are a part is close to a star, or becomes heated because one clump collides with another, the temperature of the molecules may rise considerably, perhaps to several thousand degrees above absolute zero. In these cases, the collisions between gas molecules are correspondingly more energetic, and molecules may be set to vibrating as well as rotating. For example, a carbon monoxide molecule, CO, vibrates to-and-fro as if the two atoms are connected by a coiled spring. A vibrating molecule also eventually slows down and loses energy (unless it is involved in further collisions) by emitting radiation that is again specific to that particular molecule. In the example of CO, that radiation has a wavelength of about 4.7 micrometers (18.5 × 10 −5 inches), the detection of which necessitates the use of large telescopes that are sensitive to infrared radiation.

The Milky Way, like all other galaxies, was formed from intergalactic gas that was essentially atomic. So where do the molecules come from? One can deduce that they are not left over from the processes that formed the Milky Way because scientists can detect molecules in regions in which they are (currently) being rapidly destroyed; therefore there must be a formation process in operation now. For example, the hydroxyl molecule, OH, can be observed in rather low density interstellar gas regions (containing about 100 H atoms per cubic centimeter) in which it is being destroyed by stellar radiation in a time frame, typically, of ten thousand years. This seems a long time but because the Galaxy has been in existence for a much longer time (about 15 billion years), the OH radicals (and many other species) must have been formed relatively recently in the Galaxy’s history.

Simple collisions between O and H atoms do not lead to the formation of OH molecules, because the atoms bounce apart before they are able to form a chemical bond. Similarly, low temperature collisions between O atoms and H 2 molecules are also unreactive. Astronomers have now determined that much of the chemistry of interstellar space occurs via ion-molecule reactions. Cosmic rays (fast-moving protons and electrons pervading all of interstellar space) ionize molecular hydrogen (H2) and the resulting ions (H2+ ) react quickly with more H2 to form other ions (H3+ ). The H3+ ions drive a chemistry that consists of simple two-body reactions. The extra proton in H3+ is quite weakly bound (relative to the bonding of one proton to another in H2); in a collision an H3+ molecule easily donates its proton to some other species, creating a new molecule. For example, an H3+ ion reacts with an O atom to give OH+ , a new species and the OH+ then reacts with H2 molecules to make, successively, H2 O+ and H3 O+ ions.

This process of H abstraction finishes here, because the O+ ion in H3 O+ has saturated all its valencies with respect to H atoms. However, the H3O+ ion has a strong attraction for electrons because of its positive charge, and the ion-electron recombination leads to dissociation of the ion-electron complex into a variety of products, including OH (hydroxyl) and H2 O (water). Other exchange reactions occur; for example, CO may be formed through the neutral exchange. Similar ion-molecule reactions drive the chemistries of other atoms, such as C and N, to yield ions such as CH3+ and NH3+ . These ions can then react with other species to form larger and more complex molecules. For example, methanol (CH3OH) may be formed by the reaction of CH3+ ions with H 2 O molecules, followed by recombination of the product of that reaction with electrons.  

Ion-molecule reactions, followed by ion-electron recombinations and supplemented by neutral exchanges, are capable of forming the majority of the observed interstellar molecular species. Very large gas-phase reaction networks, involving some hundreds of species interacting in some thousands of chemical reactions, are routinely used to describe the formation of the observed interstellar molecules in different locations in models of interstellar chemistry.

The dust has several important chemical roles. Obviously, it may shield molecules from the destructive effects of stellar radiation. It also has more active roles. We have seen that free atoms in collision may simply bounce apart before they can form a chemical bond. By contrast, atoms adsorbed on the surface of a dust grain may be held together until reaction occurs. It is believed that molecular hydrogen is formed in this way (i.e., through heterogeneous catalysis) and is ejected from dust grain surfaces into the gas volume with high speed and in high states of vibration and rotation. Other simple molecules, such as H2 O, CH4, and NH3, are also likely to form in this way.

In the denser clumps where the gas is very cold, the dust grains are also at a very low temperature (around 10 degrees above absolute zero). Gas phase molecules colliding with such grains tend to stick to their surfaces, and over a period of time the grains in these regions accumulate mantles of ice: mostly H2O ice, but also ices containing other molecules such as CO, CO2, and CH3 OH. Astronomers can detect these ices with spectroscopy. For example, water ice molecules absorb radiation at a wavelength about 3.0 micrometers (11.8 × 10−5 inches), having to do with the O–H vibration in H2O molecules; the molecules do not rotate because they are locked into the ice. In instances in which such ice-coated dust grains lie along a line of sight toward a star that shines in the infrared, this 3.0 micrometer (11.8 × 10−5 inch) absorption is very commonly seen.

Interstellar solid-state chemistry can occur within these ices. Laboratory experiments have shown that ices of simple species such as H2 O, CO, or NH3 can be stimulated by ultraviolet radiation or fast particles (protons, electrons) to form complex molecules, including polycyclic aromatic hydrocarbons (PAHs) containing several benzene-type rings. The detection by astronomers of free interstellar benzene (C6 H6) in at least one interstellar region suggests that this solid-state chemistry may be the route by which these molecules are made.

The primary role that interstellar molecules play is a passive one: Their presence in regions so obscured by dust that we cannot see into them using optical telescopes is used to probe these regions. The most dramatic example of this is the discovery of the so-called giant molecular clouds in the Milky Way and other galaxies via the detection of the emission of 2.6 micrometers (10.2 × 10−5 inches) wavelength radiation by CO molecules present in these clouds. The existence of these huge gas clouds, containing up to a million times the mass of the Sun, was not suspected from optical observations because these clouds are completely shrouded in dust. However, radio astronomy has shown that these clouds are the largest nonstellar structures in the Galaxy, and that they will provide the raw material for the formation of millions of new stars in future billions of years of the Galaxy’s evolution.

The radiation from molecules that we detect can represent a significant loss of energy from an interstellar cloud. Some molecules are very effective coolants of interstellar gases and help to maintain the temperatures of these gases at very low values. This cooling property is very important in clumps of gas that are collapsing inward under their own weight. If such a collapse can continue over vast stretches of time, then ultimately a star will form. In the early stages, it is important that the clumps remain cool; otherwise the gas pressure might halt the collapse. In these stages, therefore, the cooling effect of the molecules’ emission of radiation is crucial. The formation of stars like the Sun is possible because of the cooling effect of molecules. Interstellar chemistry is therefore one factor determining the rate of star formation in the Galaxy. Astrochemists have shown that it takes about one million years for the molecules of a collapsing cloud to be formed; this is about the same amount of time as that required for the collapse itself to become established. The accompanying image illustrates a region of star formation in the Galaxy.

Astrochemistry also has a role that is particularly significant to the human species here on planet Earth. The planet was formed as a byproduct of the formation of the star that is the Sun, and is in effect the accumulation of dust grains that were the debris of large chunks of matter that subsequently impacted and stuck together.: Its aim is to study the transport of prebiological material in the Galaxy and the development of life within suitable environments in the universe. Earth is still subject to the occasional impacts of debris left over from the formation of the solar system. These impacts, now seen as a source of potential danger, in fact once brought prebiotic material to Earth. The oceans arose from the arrival of icy comets, and carbon, nitrogen, and elemental metals were brought by asteroid impacts. These elements and others are necessary for life on Earth, and a new discipline, astrobiology, is coming into being

Dr. Badruddin Khan teaches Chemistry in the University of Kashmir, Srinagar, India.

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0:15 – Make low calorie rice
1:22 – Keep your fruit from oxidizing and turning brown
2:32 – Tenderize your meat quickly

Reactions is back with another round of chemistry life hacks. Our latest episode brings chemistry to the kitchen, and features science-backed tips to cook rice with fewer calories, get extra juicy chicken (when you don’t have time to marinate) and keep sliced fruit from browning too quickly. Watch the video and find out how to use chemistry to give your food a flavor boost.

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Producer/Writer: Kirk Zamieroski
Executive Producer: Adam Dylewski
Scientific consultants:
Dan Souza
Darcy Gentleman, Ph.D.
Kyle Nackers

Sources:
Low-cal rice:
https://www.acs.org/content/acs/en/pressroom/newsreleases/2015/march/new-low-calorie-rice-could-help-cut-rising-obesity-rates.html
https://www.washingtonpost.com/news/wonk/wp/2015/03/25/scientists-have-figured-out-a-simple-way-to-cook-rice-that-dramatically-cuts-the-calories/?utm_term=.0afcccf3e963
http://apjcn.nhri.org.tw/server/APJCN/24/4/620.pdf

Fruit for later:
Hack – http://www.seriouseats.com/2015/09/how-to-prevent-apple-pear-browning.html
Browning – http://hortsci.ashspublications.org/content/45/8/1150.full
http://extension.psu.edu/food/preservation/tools/supplies/ingredients/ingredients-used-in-home-food-preservation
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4444905/

Timely tenderizer:
Tenderizer hack – http://drgrub.com/tag/american-food-2/
Meats and Proteins – http://onlinelibrary.wiley.com/doi/10.1111/1541-4337.12243/full
http://www.businessinsider.com/how-to-use-baking-soda-in-marinades-2016-5
https://www.ncbi.nlm.nih.gov/pubmed/22056073

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Watch “The Statue of Liberty’s True Colors?”

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What Does Starvation Do To The Body?

We all know what hunger feels like, but what happens to our bodies if we stop eating? What exactly is the science behind starvation?

Is The North Korean Government To Blame For Starving Citizens? ►►►►http://bit.ly/1S0wnJt
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Read More:
How Long Can a Person Survive Without Food?
http://www.scientificamerican.com/article/how-long-can-a-person-sur/
“The duration of survival without food is greatly influenced by factors such as body weight, genetic variation, other health considerations and, most importantly, the presence or absence of dehydration. For total starvation in healthy individuals receiving adequate hydration, reliable data on survival are hard to obtain.”

The Psychology of Hunger
http://www.apa.org/monitor/2013/10/hunger.aspx
“In November 1944, 36 young men took up residence in the corridors and rooms of the University of Minnesota football stadium. They were not members of the football team. Rather, they were volunteers preparing for a nearly yearlong experiment on the psychological and physiological effects of starvation. Known as the Minnesota Starvation Experiment, the study was a project of the newly established Laboratory of Physiological Hygiene at the University of Minnesota, an interdisciplinary research institution with an emphasis on nutrition and human biology.”

Brain Foods: The Effects of Nutrients on Brain Function
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2805706/
“It has long been suspected that the relative abundance of specific nutrients can affect cognitive processes and emotions. Newly described influences of dietary factors on neuronal function and synaptic plasticity have revealed some of the vital mechanisms that are responsible for the action of diet on brain health and mental function. Several gut hormones that can enter the brain, or that are produced in the brain itself, influence cognitive ability.”
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Chemistry Dissertation Help: Chemistry is subject which needs a sound attention to complete any kind of work like dissertation. A mere class is not sufficient to teach or guide the students how to make a perfect dissertation. Because there is only one teacher for many students so only few students can able to catch the topic. What about the rest of the students? Those pupils who are unable to understand a topic in the class? Here is the solution, Chemistry Dissertation Help.  Chemistry Dissertation Help provides chemistry based Dissertation for school level to college level. If the students posses a personal computer, internet connection, headphone or microphone they can access this online tutorial service.

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Conclusion:Chemistry Dissertation is one such service provider that can easily meet your expectations levels as compared to other service providers. This is the reason why they make it a point to thoroughly check for level of knowledge and education in Chemistry that prospective tutors possess and also their levels of communication and psychological skills that will aid in providing better tutorial services. The aim is to always submit and meet targeted deadlines to avoid any inconvenience to students. Pricing too is structured bearing in mind concerns that students, parents and guardians share regarding value for money for services rendered.

Homework Help for party goers is important as it enables them to get homework done on time and gives them a basic understanding and they get to freak out as well. For more information visit at http://www.chemistryhomeworkhelp.org/

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Did you know that thousands of precious paintings around the world are generating soap beneath their surfaces?

Art conservators struggle with microscopic eruptions in masterpieces
http://cen.acs.org/articles/94/i21/Art-conservationists-struggle-microscopic-eruptions.html
↓↓More info and references below↓↓

A huge thanks to Rijks Museum conservator Petria Noble and independent conservation scientist Jaap Boon.

If this episode leaves you wanting more chemistry goodness, check out the featured resources below.

Van Gogh’s Fading Colors Inspire Scientific Inquiry
http://cen.acs.org/articles/94/i5/Van-Goghs-Fading-Colors-Inspire.html

Cleaning Acrylics
http://cen.acs.org/articles/89/i42/Cleaning-Acrylics.html

Speaking of Chemistry is a production of Chemical & Engineering News (C&EN), the weekly news magazine of the American Chemical Society.

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The 2016 Nobel Prizes: Chemistry and Physics!

This Nobel Prize season, dive into the world of the super small for physics and chemistry. It’s where the nanocars roam and phase transitions get really weird.

Learn more about this year’s nobel prizes: https://www.youtube.com/watch?v=_takaZB1-vg

Learn more about semiconductors: https://www.youtube.com/watch?v=kdy3RsZk7As

Hosted by: Michael Aranda
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Sources:
Chemistry
https://www.nobelprize.org/nobel_prizes/chemistry/laureates/2016/popular-chemistryprize2016.pdf

http://www.vox.com/2016/10/5/13171850/2016-nobel-prize-chemistry
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4515087/

Physics
https://www.nobelprize.org/nobel_prizes/physics/laureates/2016/popular-physicsprize2016.pdf
https://www.nobelprize.org/nobel_prizes/physics/laureates/2016/advanced-physicsprize2016.pdf
http://www.vox.com/science-and-health/2016/10/4/13155916/2016-nobel-prize-physics
An Oxford University professor explains this year’s Nobel Prize in Physics in terms a high-school student would understand
https://www.sciencenews.org/article/physics-edge

Image Sources:
https://commons.wikimedia.org/wiki/File:Papain_enzyme.png
https://commons.wikimedia.org/wiki/File:Phase-diag2.svg
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What Might Trump Mean for Chemistry? — Speaking of Chemistry

As Donald Trump becomes president, huge questions remain about his policies affecting the central science. So we’ve started looking for answers. Visit C&EN for more comprehensive coverage: http://cen.acs.org/articles/95/i3/US-science-policy-big-shift.html
↓↓More info and references below↓↓

While presidents tweet, money talks. In this episode, we look how Trump’s economic stances could affect the dollars and cents of chemistry. Huge thanks to Kevin Trenberth and Cal Dooley for their help with this video. Check out the links below for more information.

Kevin Trenberth, Distinguished Senior Scientist | NCAR
http://www.cgd.ucar.edu/staff/trenbert/

The American Chemistry Council
https://www.americanchemistry.com/

For U.S. science policy, big shift ahead | C&EN
http://cen.acs.org/articles/95/i3/US-science-policy-big-shift.html

Historical Trends in Federal R&D | AAAS
https://www.aaas.org/page/historical-trends-federal-rd

Scientists are frantically copying U.S. climate data, fearing it might vanish under Trump | WaPo
https://www.washingtonpost.com/news/energy-environment/wp/2016/12/13/scientists-are-frantically-copying-u-s-climate-data-fearing-it-might-vanish-under-trump/

Trump’s space policy reaches for Mars and the stars | Space News

Op-ed | Trump’s space policy reaches for Mars and the stars

Earth scientists are freaking out. NASA urges calm | Space News

Earth scientists are freaking out. NASA urges calm.

Trump promises to ‘lift the restrictions on American energy’ | LA Times
http://www.latimes.com/politics/la-fi-trump-fracking-20160922-snap-story.html

Earth data visualizations are all from NASA. Check them out here http://climate.nasa.gov/resources/graphics-and-multimedia/

Speaking of Chemistry is a production of Chemical & Engineering News (C&EN), the weekly news magazine of the American Chemical Society.
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The Chemistry of Fried Food

You know it, and you love it. Fried food! But there’s more to fried dishes than just plopping food into hot oil. You have to know what’s up with the food you’re cooking and what oils will work best for you dish.

Hosted by: Olivia Gordon
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Sources:
General:
http://www.ncbi.nlm.nih.gov/pubmed/19595388 (I got a pdf of this, which I can send to you via email)
http://cst.ur.ac.rw/library/Food%20Science%20books/batch1/Marcel%20Dekker,.Food%20Chemistry,%203rd%20Edition..pdf (frying starts at page 292)
Fair Food: The Science of Deep-Frying
http://www.npr.org/sections/thesalt/2016/03/24/470396393/fry-and-fry-again-the-science-secrets-to-the-double-fry
http://www.fsis.usda.gov/wps/portal/fsis/topics/food-safety-education/get-answers/food-safety-fact-sheets/safe-food-handling/deep-fat-frying-and-food-safety/ct_index
http://www.huffingtonpost.com/amanda-greene/back-to-basics-the-scienc_b_3276776.html
http://www.finecooking.com/item/48328/the-science-of-frying
http://www.encyclopedia.com/topic/Frying.aspx

Batter:
http://www.ncbi.nlm.nih.gov/pubmed/20623702
http://www.scientificamerican.com/article/beer-batter-is-better/
http://www.livestrong.com/article/530119-when-deep-frying-how-is-batter-different-with-milk-or-eggs/
http://www.foodarts.com/tools/equipment/13431/the-frying-game
https://www.finedininglovers.com/stories/what-is-tempura-batter/
http://www.finecooking.com/articles/light-delicate-tempura.aspx?pg=1
http://www.livescience.com/33128-why-does-beer-foam-.html

Oils:
http://www.heart.org/HEARTORG/HealthyLiving/HealthyEating/Nutrition/Saturated-Fats_UCM_301110_Article.jsp#.V-g7CpMrLVo
http://www.mayoclinic.org/healthy-lifestyle/nutrition-and-healthy-eating/expert-answers/cooking-oil/faq-20058170
http://www.health.harvard.edu/staying-healthy/the-truth-about-fats-bad-and-good
https://authoritynutrition.com/healthiest-oil-for-deep-frying/
http://www.bbc.com/news/magazine-33675975
http://onlinelibrary.wiley.com/doi/10.1111/j.1750-3841.2007.00352.x/full?wol1URL=/doi/10.1111/j.1750-3841.2007.00352.x/full&regionCode=US-OH&identityKey=b97a5e3f-f919-4eaf-a79b-f49f55337a2c
http://www.foodarts.com/tools/equipment/13431/the-frying-game

Images: https://commons.wikimedia.org/wiki/File:Deep_Fried_Oreo.JPG
Deep Fryer: https://commons.wikimedia.org/wiki/File:Frituren.jpg
Chicken Bubbling: https://commons.wikimedia.org/wiki/File:Deep_frying_chicken_upper_wing.JPG
Donuts: https://commons.wikimedia.org/wiki/File:Jack%27s_Donuts.jpg
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Supermarket tomatoes account for nearly 10% of produce sales in the U.S., but they taste terrible. What can be done to make them great again? Read more at http://cen.acs.org/articles/95/i5/flavor-facelift-supermarket-tomatoes.html?utm_source=YouTube&utm_medium=Social&utm_campaign=CEN&utm_content=Tomato
↓↓More info and references below↓↓

A huge thanks to the tomato researchers Harry Klee and Jim Giovannoni who helped us with this episode’s science. You can learn more about their work in the description below, too. Thanks for watching and don’t forget to subscribe and share.

If this episode leaves you wanting more chemistry goodness, check out the featured resources below.

A flavor face-lift for supermarket tomatoes | C&EN
http://cen.acs.org/articles/95/i5/flavor-facelift-supermarket-tomatoes.html

Chilling tomatoes blocks production of flavor-making enzymes | C&EN
http://cen.acs.org/articles/94/i42/Chilling-tomatoes-blocks-production-flavor.html

Why Supermarket Tomatoes Taste Bland | C&EN
http://cen.acs.org/articles/90/web/2012/06/Supermarket-Tomatoes-Taste-Bland.html

Speaking of Chemistry is a production of Chemical & Engineering News (C&EN), the weekly news magazine of the American Chemical Society.

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If you own a laptop computer, chances are very very good that it is probably powered by a lithium-ion (Li-ion) battery. This battery type has found application in a wide variety of consumer electronics, including PDAs and cell phones. They have gained widespread popularity due to economic and technical reasons, particularly their high charge to weight ratio.

Lithium-ion batteries have replaced the nickel-cadmium (NiCd) batteries that were first used to power laptop computers and the nickel-metal hydride (NiMH) batteries that superseded the NiCd laptop battery technology. They have dominated today’s rechargeable battery market for laptop computers because they are much lighter than the other types of laptop batteries, they retain their charge longer than the other technologies and because they do not suffer from the memory effect phenomenon. A typical lithium-ion battery has two times the energy density of a standard nickel cadmium battery. Additionally, lithium-ion batteries have a single cell voltage of 3.6 volts as compared to 1.2 volts per cell of nickel-cadmium batteries.

However, the disadvantages associated with lithium-ion batteries include: the possibility that a failed battery pack can ignite under adverse conditions, they are more sensitive to high temperature environments than the other battery technologies in their ability to retain their charge, they may fail if they are completely discharged, and the inherit chemistry of the battery leads to degradation with age as opposed to the stronger correlation between battery failures and charge/discharge cycles of the older battery chemistries. Lithium-ion computer batteries also require that protection circuitry be incorporated into the battery pack to monitor the battery charge and to provide safe voltage and current levels, as well as ensuring that the temperature of the battery remains in a safe operating range.

Cylindrical lithium-ion battery cells are generally tubular in shape, much like the shape of standard alkaline batteries. Several cells are enclosed in a plastic housing and the individual cells are connected in a manner to provide the proper output voltage and to maximize storage capacity (rated in milliamp-hours). Prismatic shaped lithium-ion cells are also available, but they are much smaller and are typically used in devices such as cell phones where weight and space is a prime consideration.

There are several things that affect the life of a lithium-ion laptop battery. Battery degradation is hastened by heat, so storing the battery in a cool environment will prolong its life. Manufacturers typically recommend a storage temperature of approximately 60°F for the long-term storage of lithium-ion batteries. These batteries, as stated previously, do not retain a memory from partial discharge cycles, so full discharge cycles are not required. In fact, partial cycling of the battery will help extend its life. Lithium-ion batteries do have a limited lifetime like the older battery technologies, but this is relatively independent of their charging cycles and is chiefly related to their age. A typical battery will last only 2 to 3 years. This is true even if the battery remains unused so it is important not to purchase a replacement laptop battery until it is ready to be put into service.

The author has established a website for replacement laptop batteries that provides tips and buying advice regarding cheap laptop batteries. An in-depth article on laptop battery ratings discusses the voltage and milliamp-hours specifications that are two of the chief considerations in the choice of a replacement laptop battery.

Organic chemistry is a branch within chemistry which deals with the study of chemical compounds containing carbon; their formation, their processes, properties, reactions and structure. Formerly, it was popular belief that it was very difficult to artificially synthesize compounds from living organisms. When it was realized later, that even those compounds could be treated in ways similar to the inorganic ones, in laboratories and through artificial processes, organic chemistry gained momentum.

Organic compounds are usually covalently bond which allows it to form unique structures in the form of long chains and rings. As opposed to inorganic compounds, organic compounds melt, decompose, sublime below 300 degrees. Solubility of organic compounds depends on solvent type and on functional groups. Perkin’s attempt to manufacture quinine which resulted in organic dye generated a lot of interest in organic chemistry.

Life depends on inorganic chemistry as well, and it is not always that organic compounds can be related to all the life processes taking place.

The production of organic molecules may include processes not including life. These include those enzymes that require other metals, like iron, rather than carbon. Elemental carbon and a few classes of carbon compounds are also considered inorganic. Organic compounds can be put to many uses in a number of applications. They are used in products like paints, plastics, foods, explosives and also form the basis of many natural and earthly life processes. They may even act as catalysts in biochemical reactions, owing to their varying reactivity.

The petrochemical industry was created by the discovery of petroleum and its separation into fractions. Conversion of compounds using different chemical processes also gave a boost to the petrochemical industry. To explain classification, in organic chemistry it is required that the relative arrangement of atoms within a molecule must be added for a full description. In short, organic substances are classified on the basis of their molecular arrangement and other constituents.

Compounds have been divided into functional groups and have further been distributed into sub classes. There are two major categories of compounds; namely the aliphatic compounds and the cyclic compounds.
The aliphatic compounds are further divided into 3 groups, homologous series, paraffin alkenes without any double or triple bonds or olefins alkenes with the a single or double bond and acetylenes alkenes with triple bonds. Aliphatic compounds may either be straight chained or branch chained ones which further affects characteristics like octane number or cetin number in petroleum chemistry.

Cyclic compounds maybe saturated or unsaturated. The cyclic hydrocarbons can be divided into two groups namely; salicylic and aromatics. The former type exists in the form of large rings while aromatics contain conjugated double bonds e.g. benzene.

In organic chemistry, carbon is believed to have the capability of forming certain compounds whose molecules can form a network by attaching themselves to each other. This process is known as polymerization and the chain that is formed is called polymers while monomer remains the source compound. Polymers can be artificially produced and are called industrial polymers while those occurring naturally or synthetic polymers are referred to as biopolymers e.g. Teflon, polythene, nylon etc. All these may be present in different varieties varying on the basis of compositions used to produce them.

Another important area of study that falls within organic chemistry is the bi molecular chemistry. It is of particular interest to biochemists. Biochemistry involves the study of the long chains bio polymers and amino acids, carbohydrates etc., basically, the multi-functional group molecules in living organisms. Animal biochemistry contains small molecule intermediates required to produce energy with the use of common hydrocarbons found in animals.

Fullerenes are among those compounds which have electronic properties due to their spherical structure. Organic compounds containing bonds of carbon along with nitrogen, oxygen and halogen are also classified within organic chemistry.

Organic reactions are chemical reactions which involve organic compounds and the reactions the compounds undergo are determined by the functional groups. Organic chemistry encompasses the study of all such reactions and is an applied science used in many areas of study, especially to design synthesis, analyze and put it to practical use.

Segun Olowookere recently started his own clothing company called Lowooke who speciallise in designing, producing and distributing a range of clothing aimed at the urban and youth market. The apparel that Lowooke sell is produced using organic materials that have been ethically sourced. You can view their range of Urban Clothing London at http://www.lowooke.com/shop/

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