Radical (chemistry)

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In chemistry, radicals (often referred to as free radicals) are atoms, molecules, or ions with unpaired electrons on an otherwise open shell configuration. These unpaired electrons are usually highly reactive, so radicals are likely to take part in chemical reactions. Radicals play an important role in combustion, atmospheric chemistry, polymerization, plasma chemistry, biochemistry, and many other chemical processes, including human physiology. For example, superoxide and nitric oxide regulate many biological processes, such as controlling vascular tone. "Radical" and "free radical" are frequently used interchangeably, although a radical may be trapped within a solvent cage or be otherwise bound. The first organic free radical identified was triphenylmethyl radical, by Moses Gomberg in 1900 at the University of Michigan.

Historically, the term radical has also been used for bound parts of the molecule, especially when they remain unchanged in reactions. These are now called functional groups. For example, methyl alcohol was described as consisting of a methyl "radical" and a hydroxyl "radical". Neither are radicals in the modern chemical sense, as they are permanently bound to each other, and have no unpaired, reactive electrons. They can, however, be observed as radicals in mass spectrometry after breaking down the substance with a hail of energetic electrons.

For more information about Radical (chemistry), read the full article at Wikipedia.
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News tagged with free radicals

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Road rage: Fuel vapor heightens aggression

Medicine & Health / Research

created Nov 24, 2009 | popularity 4.5 / 5 (4) | comments 1

Outrageous prices may not be the only thing causing anger at the petrol pumps. A new study, published in the open access journal BMC Physiology, has shown that rats exposed to fumes from leaded and unleaded gasoline become ...


Tiny particles can deliver antioxidant enzyme to injured heart cells

Tiny particles can deliver antioxidant enzyme to injured heart cells

Chemistry / Polymers

created Nov 16, 2009 | popularity 5 / 5 (2) | comments 0

Researchers at Emory University and the Georgia Institute of Technology have developed microscopic polymer beads that can deliver an antioxidant enzyme made naturally by the body into the heart.


Now hear this: Mouse study sheds light on hearing loss in older adults

Medicine & Health / Genetics

created Nov 09, 2009 | popularity 5 / 5 (1) | comments 0

(PhysOrg.com) -- Becoming "hard of hearing" is a standard but unfortunate part of aging: A syndrome called age-related hearing loss affects about 40 percent of people over 65 in the United States, and will afflict an estimated ...


Living longer and happier

Medicine & Health / Research

created Aug 19, 2009 | popularity 5 / 5 (5) | comments 2

A new study from the University of Missouri may shed light on how to increase the level and quality of activity in the elderly. In the study, published in this week's edition of Public Library of Science - ONE, MU resear ...


Chocolate cuts death rate in heart attack survivors: study

Medicine & Health / Research

created Aug 13, 2009 | popularity 4.4 / 5 (9) | comments 4

Heart attack survivors who eat chocolate two or more times per week cut their risk of dying from heart disease about threefold compared to those who never touch the stuff, scientists have reported.


Study: Infant inhalation of ultrafine air pollution linked to adult lung disease

Medicine & Health / Health

created Jul 22, 2009 | popularity not rated yet | comments 0

Stephania Cormier, PhD, Associate Professor of Pharmacology at LSU Health Sciences Center New Orleans, has shown for the first time that early exposure to environmentally persistent free radicals (present in airborne ultrafine ...


Scientists track chemical changes in cells as they endure extreme conditions

Chemistry / Biochemistry

created Jul 07, 2009 | popularity 4.5 / 5 (2) | comments 1

One of nature's most gripping feats of survival is now better understood. For the first time, scientists from the U.S. Department of Energy's Lawrence Berkeley National Laboratory observed the chemical changes in individual ...


How oxidative stress may help prolong life

How oxidative stress may help prolong life

Medicine & Health / Genetics

created May 29, 2009 | popularity 3.5 / 5 (2) | comments 0

(PhysOrg.com) -- Oxidative stress has been linked to aging, cancer and other diseases in humans. Paradoxically, researchers have suggested that small exposure to oxidative conditions may actually offer protection ...


Toward a systems biology map of iron metabolism

Chemistry / Biochemistry

created Apr 28, 2009 | popularity 5 / 5 (2) | comments 0

Scientists at the Wake Forest University School of Medicine, the University of Manchester in the United Kingdom, and the Virginia Bioinformatics Institute at Virginia Tech have taken the first steps toward constructing a ...


Source of major health benefits in olive oil revealed

Medicine & Health / Research

created Apr 02, 2009 | popularity 4.5 / 5 (4) | comments 0

Scientists have pinned down the constituent of olive oil that gives greatest protection from heart attack and stroke. In a study of the major antioxidants in olive oil, Portuguese researchers showed that one, DHPEA-EDA, protects ...


Forget the antioxidants? Researchers cast doubt on role of free radicals in aging

Biology /

created Feb 17, 2009 | popularity 4.5 / 5 (10) | comments 5

For more than 40 years, the prevailing explanation of why we get old has been tied to what is called oxidative stress. This theory postulates that when molecules like free radicals, oxygen ions and peroxides build up in cells, ...


Radical Scavengers in Red Smear Cheeses

Chemistry /

created Dec 15, 2008 | popularity 3 / 5 (3) | comments 0

(PhysOrg.com) -- Carotenoids not only give carrots and red smear cheeses, such as Munster, Limburger, and Romadur, their characteristic red color, but they also protect organisms from oxidative stress. A research team headed ...


Cutting calories could limit muscle wasting in later years

Medicine & Health / Health

created Sep 16, 2008 | popularity 4.7 / 5 (21) | comments 0

Chemical concoctions can smooth over wrinkles and hide those pesky grays, but what about the signs of aging that aren't so easy to fix, such as losing muscle mass? Cutting calories early could help, say University of Florida ...


Killer carbs -- Monash scientist finds the key to overeating as we age

Medicine & Health / Other

created Aug 21, 2008 | popularity 4.2 / 5 (39) | comments 4

A Monash University scientist has discovered key appetite control cells in the human brain degenerate over time, causing increased hunger and potentially weight-gain as we grow older.


Persistent Free Radicals

Newly detected air pollutant mimics damaging effects of cigarette smoke

Chemistry /

created Aug 17, 2008 | popularity 4.4 / 5 (29) | comments 1

A previously unrecognized group of air pollutants could have effects remarkably similar to harmful substances found in tobacco smoke, Louisiana scientists are reporting in a study scheduled for presentation ...