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What does letter H represent?
h, eighth letter of the alphabet. It corresponds to Semitic cheth and Greek eta (Η). It may derive from an early symbol for fence. In the early Greek alphabets a form with three horizontal bars and the simpler form H were both widely distributed.
How old is the letter H?
The letter 'H' came from the Egyptians and used as a symbol for fence. It made a breathy sound when pronounced so early academicians thought that it was not necessary and the British and Latin scholars eventually dropped the letter H from the English alphabet by around 500 AD.
How do you spell H phonetically?
Name in English For most English speakers, the name for the letter is pronounced as /eɪtʃ/ and spelled "aitch" or occasionally "eitch". The pronunciation /heɪtʃ/ and the associated spelling "haitch" is often considered to be h-adding and is considered nonstandard in England.
Why is the letter H pronounced aitch?
Usage (language): The name of the letter h is based on French (h)ache, in which the initial h is not pronounced. In imitation of the French, the English name is commonly aitch, but this means the name does not contain the sound of the letter.
What letter is 0 in the alphabet?
O, or o, is the fifteenth letter in the ISO basic Latin alphabet and the fourth vowel letter in the modern English alphabet. Its name in English is o (pronounced /ˈoʊ/), plural oes.
Which is the most beautiful letter in alphabet?
'S' is the most beautiful letter of alphabets. It is beneficial in a way that we can use it upside down as well.
How do you say H in British English?
0:070:58The Letter H - RP British Accent Pronunciation practice - YouTubeYouTubeStart of suggested clipEnd of suggested clipThe correct pronunciation of H is H. Try not to over emphasize the letter H by using a H sound HD HDMoreThe correct pronunciation of H is H. Try not to over emphasize the letter H by using a H sound HD HD.
How do you write H?
1:242:16Alphabet Writing lesson for children | The Singing Walrus - YouTubeYouTubeStart of suggested clipEnd of suggested clipLet's try it again down up around and down now you try now check if you did it. Right well done nowMoreLet's try it again down up around and down now you try now check if you did it. Right well done now you know how to write the letter h. Next time we'll write the letter.
How do you say H in Australia?
How one should pronounce the eighth letter of the alphabet—H—is one such point of contention. In Australia, the common line of thinking seems to be there are two ways to pronounce it—'aitch', and 'haitch'.
How old is the letter J?
I understand that the letter "J" is relatively new — perhaps 400–500 years old.
Is Haitch correct?
First, you won't find 'haitch' in the dictionary, only the correct spelling aitch. The name of the letter comes from Old French ache of the 1500s and first spelt so in English, when it was related to the Old English word ache, from æce. At this time it was pronounced "ache" or "aitch".
How do you spell Z?
0:000:10Basic English: How to Pronounce the Letter Z - YouTubeYouTubeStart of suggested clipEnd of suggested clipZ Z Z Z.MoreZ Z Z Z.
Overview
Hydrogen is the chemical element with the symbol H and atomic number 1. Hydrogen is the lightest element. At standard conditions hydrogen is a gas of diatomic molecules having the formula H2. It is colorless, odorless, tasteless, non-toxic, and highly combustible. Hydrogen is the most abundant chemical substance in the universe, constituting roughly 75% of all normal matter. Stars s…
Properties
Hydrogen gas (dihydrogen or molecular hydrogen) is highly flammable:
2 H2(g) + O2(g) → 2 H2O(l) + 572 kJ (286 kJ/mol)
The enthalpy of combustion is −286 kJ/mol.
Hydrogen gas forms explosive mixtures with air in concentrations from 4–74% and with chlorine at 5–95%. The explosive reactions may be triggered by spark…
History
In 1671, Robert Boyle discovered and described the reaction between iron filings and dilute acids, which results in the production of hydrogen gas. In 1766, Henry Cavendish was the first to recognize hydrogen gas as a discrete substance, by naming the gas from a metal-acid reaction "inflammable air". He speculated that "inflammable air" was in fact identical to the hypothetical substance called "phl…
Cosmic prevalence and distribution
Hydrogen, as atomic H, is the most abundant chemical element in the universe, making up 75 percent of normal matter by mass and more than 90 percent by number of atoms. (Most of the mass of the universe, however, is not in the form of chemical-element type matter, but rather is postulated to occur as yet-undetected forms of mass such as dark matter and dark energy. ) This element …
Production
H 2 is produced in chemistry and biology laboratories, often as a by-product of other reactions; in industry for the hydrogenation of unsaturated substrates; and in nature as a means of expelling reducing equivalents in biochemical reactions.
The electrolysis of water is a simple method of producing hydrogen. A current is run through the water, and gaseous oxygen forms at the anode while gaseous h…
Applications
Large quantities of H 2 are used in the "upgrading" of fossil fuels. Key consumers of H 2 include hydrodealkylation, hydrodesulfurization, and hydrocracking. Many of these reactions can be classified as hydrogenolysis, i.e., the cleavage of bonds to carbon. Illustrative is the separation of sulfur from liquid fossil fuels:
R-S-R + 2 H2 → H2S + 2 RH
Biological reactions
H2 is a product of some types of anaerobic metabolism and is produced by several microorganisms, usually via reactions catalyzed by iron- or nickel-containing enzymes called hydrogenases. These enzymes catalyze the reversible redox reaction between H2 and its component two protons and two electrons. Creation of hydrogen gas occurs in the transfer of reducing equivalents produced during pyruvate fermentation to water. The natural cycle of hydrog…
Safety and precautions
Hydrogen poses a number of hazards to human safety, from potential detonations and fires when mixed with air to being an asphyxiant in its pure, oxygen-free form. In addition, liquid hydrogen is a cryogen and presents dangers (such as frostbite) associated with very cold liquids. Hydrogen dissolves in many metals and in addition to leaking out, may have adverse effects on them, such as hydrogen embrittlement, leading to cracks and explosions. Hydrogen gas leaking into externa…