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Chemical symbols

A chemical symbol    is an abbreviation that we use to indicate an element or an atom of an element. For example, the symbol for mercury is Hg ( [link] ). We use the same symbol to indicate one atom of mercury (microscopic domain) or to label a container of many atoms of the element mercury (macroscopic domain).

A jar labeled “H g” is shown with a small amount of liquid mercury in it.
The symbol Hg represents the element mercury regardless of the amount; it could represent one atom of mercury or a large amount of mercury.

The symbols for several common elements and their atoms are listed in [link] . Some symbols are derived from the common name of the element; others are abbreviations of the name in another language. Most symbols have one or two letters, but three-letter symbols have been used to describe some elements that have atomic numbers greater than 112. To avoid confusion with other notations, only the first letter of a symbol is capitalized. For example, Co is the symbol for the element cobalt, but CO is the notation for the compound carbon monoxide, which contains atoms of the elements carbon (C) and oxygen (O). All known elements and their symbols are in the periodic table in [link] (also found in [link] ).

Some Common Elements and Their Symbols
Element Symbol Element Symbol
aluminum Al iron Fe (from ferrum )
bromine Br lead Pb (from plumbum )
calcium Ca magnesium Mg
carbon C mercury Hg (from hydrargyrum )
chlorine Cl nitrogen N
chromium Cr oxygen O
cobalt Co potassium K (from kalium )
copper Cu (from cuprum ) silicon Si
fluorine F silver Ag (from argentum )
gold Au (from aurum ) sodium Na (from natrium )
helium He sulfur S
hydrogen H tin Sn (from stannum )
iodine I zinc Zn

Traditionally, the discoverer (or discoverers) of a new element names the element. However, until the name is recognized by the International Union of Pure and Applied Chemistry (IUPAC), the recommended name of the new element is based on the Latin word(s) for its atomic number. For example, element 106 was called unnilhexium (Unh), element 107 was called unnilseptium (Uns), and element 108 was called unniloctium (Uno) for several years. These elements are now named after scientists (or occasionally locations); for example, element 106 is now known as seaborgium (Sg) in honor of Glenn Seaborg, a Nobel Prize winner who was active in the discovery of several heavy elements.

Isotopes

The symbol for a specific isotope of any element is written by placing the mass number as a superscript to the left of the element symbol ( [link] ). The atomic number is sometimes written as a subscript preceding the symbol, but since this number defines the element’s identity, as does its symbol, it is often omitted. For example, magnesium exists as a mixture of three isotopes, each with an atomic number of 12 and with mass numbers of 24, 25, and 26, respectively. These isotopes can be identified as 24 Mg, 25 Mg, and 26 Mg. These isotope symbols are read as “element, mass number” and can be symbolized consistent with this reading. For instance, 24 Mg is read as “magnesium 24,” and can be written as “magnesium-24” or “Mg-24.” 25 Mg is read as “magnesium 25,” and can be written as “magnesium-25” or “Mg-25.” All magnesium atoms have 12 protons in their nucleus. They differ only because a 24 Mg atom has 12 neutrons in its nucleus, a 25 Mg atom has 13 neutrons, and a 26 Mg has 14 neutrons.

Questions & Answers

what is matter
Arinze Reply
a plot of the atomic radius against atomic number shows a periodic variation with group 1elements occupying the peaks and group 4 the troughs.plot the graph
Ngoline Reply
what is the periodic table all about
Godstime Reply
am new here looking forward on learning new stuff
Godstime
answer me please
Godstime
yeah
samuel
it's about predicting the different types of matter around us and organizing them in an elegant way
William
what is boyle law
Daniel Reply
the law states that at a constant absolute temperature the volume of a fixed of a gas is inversely proportional to the pressure of the gas...
Johnson
write short not on paper chromAtogphy
Ujunwa Reply
I am sorry, I don't understand the question. Are you referring to photospectometry, a machine that uses lightwaves to determine the chemical composition of a substance? Instead of the "coffee filter and solvent" method which is more crude, but simple enough to understand basic concepts.
Melissa
kkk
samuel
what is esterification?
Darey Reply
Esterification is the general name for a chemical reaction in which two reactants (typically an alcohol and an acid) form an ester(-COOR) as the reaction product....
Johnson
pls i dont know chemistry wat shall i do?
Chancha
Please...what do you mean by you don't know chemistry..can you explain further
Johnson
I am afraid you may end up injuring yourself working with these chemical processes with limited lab experience. Please be extremely careful. Research chem analysis, precedure and equipment.
Melissa
Kkk
samuel
Pls can I be enlighten about boys law on chemistry
samuel
how we Learn full periodic table
muhammad Reply
how
Imran
Hello guys am new here my name is Angel from Nigeria how are u guys doing?
Angel Reply
Gud am from Nigeria too my name is sav
Michael
explain the atomic orbital
Masti Reply
2nacl➡️2na+cl2 2.58.5g 22.4l
suvarthavani Reply
what is neclear energy
Moyosoreoluwa Reply
nuclear energy is the energy released during nuclear fission or fusion.especially when used to generate electricity
Inusah
How many processes to break down CARBON DIOXIDE into carbon and oxygen
Prabhakar Reply
biology is my best subject
Oseni Reply
o really
Ajila
biology quick chemistry ass
Izadora
You're in the wrong place lmao
Zeus
hi Guy
Charles
hello
daniel
hy
Kareem
How are you guys
daniel
fine and u
Kareem
were are you guys from?
Izadora
l'm from Nigeria
Kareem
Brazil
Izadora
please someone should ask question
Kareem
like what
Izadora
Am from malawi
Hele
I'm from Nigeria, my name is Vincent. what is the relationship between volume an temperature?
Vincent
who is the father of chemistry?
Vincent
hey guys I'm new to the conservation, my name is Vincent from Nigeria, how are you guys doing?
Vincent
fine
Kareem
the relationship between volume and temperature is. volume is directly proportional to temperature
Inusah
Antoine lavoisier
Ujunwa
good evening everyone my name is Maryann
Ujunwa
an acid is any substance which when dissolved in water produces hydrogen ion as its only positive ion
Ezemadu Reply
its just me or you guys also hate chemistry?
Izadora
I partially hate it
Oseni
there's some parts that I actually like to study
Izadora
sometimes
Izadora
tell me about it
Oseni
like radiation
Izadora
physics have this too
Izadora
good evening everyone my name is Maryann
Ujunwa
Why acid is sour in taste. Please don't say naturally because there are a scientific reason in all natural thing
Prabhakar Reply
since it has a negatively charge nitrogen ions
Elvis
sorry, positively hydrogen ions, which has a pH less than 7
Elvis
Corrct, as the H+ ion concentration increases acidity increases.
Aakash
because it's pH value is smaller than 7.
Raju
what is molecules
samuel
what is acid
Faree

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Source:  OpenStax, Chemistry. OpenStax CNX. May 20, 2015 Download for free at http://legacy.cnx.org/content/col11760/1.9
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