Hydrogen is a chemical element with the symbol H and atomic number 1.

It is the lightest and most abundant element, constituting about 75% of

all normal matter. The Sun is mainly hydrogen in a plasma state. Under

standard conditions, hydrogen is a gas of diatomic molecules with the

formula H2; it is colorless, odorless, non-toxic and highly combustible.

On Earth, hydrogen can exist in its gaseous state and in molecular

forms, such as with oxygen in water (H2O). The most common isotope of

hydrogen (1H) consists of one proton, one electron and no neutrons.

Hydrogen gas was first produced artificially by the reaction of acids

with metals. Henry Cavendish, in 1766–1781, identified hydrogen gas as

a distinct substance and discovered its property of producing water when

burned; its name means water-former in Greek. Its main industrial uses

include fossil-fuel processing and ammonia production for fertilizer.

Emerging uses for hydrogen include the use of fuel cells to generate

electricity.

Read more:

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Today's selected anniversaries:

1622:

Fifty-five Christians were executed in Nagasaki during the

Great Genna Martyrdom, part of persecution towards Christians in Japan

by the Tokugawa shogunate.

1858:

George Mary Searle discovered the asteroid 55 Pandora from the

Dudley Observatory near Albany, New York; it was his only asteroid

discovery.

1945:

Mike the Headless Chicken was decapitated on a farm in

Colorado; he survived another 18 months as part of sideshows before

choking to death.

2009:

Members of the Atlanta Police Department conducted a raid on a

gay bar, with patrons later alleging that their constitutional rights

had been violated and the city agreeing to pay over $1 million in

settlements.

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Wiktionary's word of the day:

posterize:

1. (transitive)

2.

3. (graphic design, photography) To inadvertently or intentionally

reduce the number of colours in (a photograph or other image), changing

a continuous gradation of tone to several regions of fewer tones with

abrupt changes from one tone to another.

4.

5. (Canada, US, basketball, slang) To score a slam dunk in basketball

against (one or more opposing players) by leaping over them; also (by

extension, sports, slang), to score a goal, a point, etc., in some other

sport against (one or more opposing players) in a spectacular manner.

6. (intransitive, graphic design, photography) To inadvertently or

intentionally reduce the number of colours in a photograph or other

image, changing a continuous gradation of tone to several regions of

fewer tones with abrupt changes from one tone to another.

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Wikiquote quote of the day:

  Instructions for living a life: Pay attention. Be astonished.

Tell about it.  

--Mary Oliver

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