Mercury
Mercury
, also known as
quicksilver
[1]
or
hydrargyrum
(pronounced hai-DRAR-j?r-?m), is a
chemical element
. Its
symbol
on the
periodic table
is
Hg
, and its
atomic number
is 80. Its
atomic mass
is 200.59.
The symbol
Hg
stands for its
Latinized
Greek
name
hydrargyrum
, meaning watery or
liquid
silver
.
The symbol for
the planet Mercury
(?) has been used for a very long time to represent the element
No one has the credit for finding mercury. It was known in ancient times. Mercury was found in
Egyptian
tombs
that are from 2000 BC.
[2]
Chinese people also knew about it long ago.
[3]
In
China
and
Tibet
, people thought using mercury would make them live longer and have better health. One of China's
emperors
,
Qin Sh? Huang Di
, is said to have been buried in a tomb with rivers of flowing mercury. He died from drinking a
mixture
of mercury and
powdered
jade
because he wanted to live forever.
[4]
[5]
However, this only made him die of
liver
failure,
poisoning
, and
brain death
. The
ancient Greeks
used mercury in
ointments
. The
Egyptians
and the
Romans
used it in
cosmetics
. These cosmetics sometimes hurt and made faces uglier.
Mercury is a silvery-white liquid
post-transition metal
. The reason for mercury being a liquid is complex. It is
heavy
; a chunk of
iron
can float on mercury. Compared to other
metals
, it does not
conduct
heat
well. However, it conducts electricity fairly well.
[6]
Mercury is the only metal with a known
melting point
(?38.83 °C) lower than
caesium
.
[7]
[8]
Mercury is one of the two elements that are
liquids
at
standard temperature and pressure
.
Bromine
is the other one.
[9]
[10]
Mercury may be seen as a
transition metal
, but it is normally seen as a post-transition metal. It is in
Group 12
of the periodic table. Mercury has seven stable (non
radioactive
)
isotopes
.
202
Hg is the most common isotope. Mercury makes a blue to
ultraviolet
color in a tube when a
spark
is passed through it. The ultraviolet light can kill germs or light
fluorescent lamp
s.
Mercury is an
unreactive
metal. It does not
corrode
in air unless
hydrogen sulfide
is also there, similar to
silver
. Mercury can
oxidize
to mercury(II) oxide when heated in air. If it is heated further, it decomposes into mercury and oxygen again. It does not dissolve in ordinary
acids
, but can dissolve in
oxidizing
acids to make mercury
salts
. It can make
amalgams
when mixed with most metals, like
aluminium
,
gold
, and
zinc
.
Iron
,
tantalum
,
tungsten
, and
platinum
do not make amalgams with mercury. Iron flasks were used to trade mercury because of this.
Mercury can dissolve large amounts of aluminium metal, making it dangerous to transport in aluminium containers. The thin layer of oxide on aluminium stops it from amalgamating (making an amalgam with) aluminium, but the oxide coating can be damaged to expose the metal. Then the aluminium metal is dissolved and oxidizes to
aluminium oxide
. The aluminium oxide forms a solid and releases the mercury, which amalgamates more aluminium. This process keeps repeating until a large amount of aluminium is dissolved.
Mercury chloride,
possibly mercury(I) chloride
Cinnabar, mercury(II) sulfide
Mercury(I) chloride as a mineral
Mercury(II) fulminate
Mercury forms
chemical compounds
in 2
oxidation states
: +1 and +2. Mercury(I) compounds are weak
oxidizing agents
and weak
reducing agents
. Most of them are colorless. They easily
disproportionate
to mercury(II) compounds and mercury metal. They react with oxygen in the air to make mercury(II) compounds. Many mercury(I) compounds do not dissolve in water.
Mercury(I) chloride
is one of the most common mercury(I) compounds. Mercury(II) compounds are strong
oxidizing agents
and very corrosive. Mercury(II) compounds are red, yellow, or colorless.
Mercury(II) oxide
and
mercury(II) chloride
are the most common mercury(II) compounds in the
laboratory
.
One thing they have in common is that they are all toxic. The soluble ones are more toxic than the insoluble ones.
Also known as mercurous compounds, these are weak
reducing agents
and weak
oxidizing agents
. Most of them do not dissolve in water, making them less toxic than mercury(II) compounds. Most of them are colorless or yellow.
- Mercury(I) bromide
, insouble white solid
- Mercury(I) chloride
, calomel, insoluble, white
- Mercury(I) fluoride
, light yellow
- Mercury(I) iodide
, a little soluble, unstable, yellow
- Mercury(I) nitrate
, very slightly soluble, white
- Mercury(I) sulfate
, light yellow solid
Also known as mercuric compounds, these are strong oxidizing agents. Most of them dissolve in water, making them very toxic. They are colorless or red.
- Mercury(II) bromide
, white solid
- Mercury(II) chloride
, white solid, corrosive sublimate
- Mercury(II) fluoride
, white solid
- Mercury(II) iodide
, somewhat soluble, bright red
- Mercury(II) oxide
, orange, yellow or red, does not dissolve in water like most oxides
- Mercury(II) nitrate
, soluble, white, used to make hats
- Mercury(II) sulfate
, white solid
- Mercury(II) sulfide
, red solid
These contain mercury reacted with a
organic
molecule. They are even more toxic than other mercury compounds since they get absorbed very easily.
Small blobs of liquid mercury as an element along with streaks of cinnabar
Another rock with liquid mercury on it
Mercury is a rare metal. It is about as common as
silver
. Mercury is not expensive like silver because the mercury is very easy to get from the places where it is found. Mercury can be found in elemental (liquid) form in nature, but this is not common. Mercury as an element is the only
liquid
that is recognized as a mineral by the
International Mineralogical Association
.
[11]
[12]
It is most often found in the form of
cinnabar
, a
mercury(II) sulfide
mineral
. The biggest deposits of cinnabar used to be found in Spain, but now are found in China. It also occurs in other minerals like
calomel
, a mercury(I) chloride mineral.
China
and
Kyrgyzstan
are the two main makers of mercury. Mines in
Italy
, the
United States
, and
Mexico
have been closed. China is opening more mines because the
European Union
wants to use
fluorescent lights
, which need mercury.
Mercury is made by roasting cinnabar in a furnace. The
sulfide
is oxidized to
sulfur dioxide
, leaving mercury behind.
Mercury has been used in
dental
fillings until it was replaced with safer materials. They are an
amalgam
of mercury with another element. An organic mercury compound called thiomersal is used to preserve
vaccines
.
[13]
Merbromin, another organic mercury compound, is used as an
antiseptic
. It has been banned in some countries like the US.
[14]
Mercury(I) chloride (also known as calomel or mercurous chloride) has been used as a
diuretic
, skin
disinfectant
, and
laxative
. Together with other mercury compounds,
Mercury(II) chloride
(also known as mercuric chloride or corrosive sublimate) was used to treat
syphilis
. The problem with this was that mercury(II) chloride is very toxic. Sometimes the symptoms of its toxicity were confused with those of the syphilis it was believed to treat.
[15]
It is also used as a disinfectant.
Blue mass
, a pill or syrup in which mercury is the main ingredient, was prescribed throughout the 1800s for different conditions such as constipation,
depression
, child-bearing and
toothaches
.
[16]
In the early 20th century, mercury was given to children once a year as a laxative and dewormer. Teething powders for infants also had it in them.
Since the 1930s some
vaccines
have contained the preservative
thiomersal
. In the body, this is changed to
ethylmercury
. At first it was thought that this mercury-based preservative can cause or trigger
autism
in children, but scientific studies could not show such a link.
[17]
Because of this, thiomersal has been removed from most U.S. vaccines recommended for children six years of age and under.
[18]
There are certain exceptions to this rule for
influenza
vaccines. In some cases, vaccines may still have very small amounts of thiomersal in them.
Cinnabar is still an important component of traditional Chinese, Tibetan, and Ayurvedic medicine. Certain countries do not allow the use of mercury or its compounds in drugs. For this reason, cinnabar has recently been replaced with less toxic products.
Today, the use of mercury in medicine has greatly declined in all respects, especially in developed countries.
Thermometers
and blood pressure devices using mercury were invented in the early 18th and late 19th centuries, respectively. Now their use is declining and has been banned in some countries, states and medical institutions. In 2002, the
U.S. Senate
passed legislation to phase out the sale of non-prescription mercury thermometers. In 2003,
Washington
and
Maine
became the first states to ban mercury blood pressure devices.
[19]
Mercury compounds are in some over-the-counter drugs, including topical antiseptics, stimulant laxatives, diaper rash
ointment
, eye drops, and nasal sprays. The
FDA
has “inadequate data to establish general recognition of the safety and effectiveness” of the mercury in these products.
[20]
Mercury is still used in some diuretics, although other things can be used for most therapeutic uses.
Mercury is also used:
In 2017 the worldwide use of mercury was less than half of what it was in 1980.
[21]
Mercury is liquid at room temperature, and
fumes
of mercury are
very poisonous
. Ingested elemental mercury is less dangerous. The biggest problems are
organic
mercury compounds which are eaten with food. As with other
heavy metals
, inorganic compounds such as
mercury(II) nitrate
are also highly toxic by ingestion (eating) or inhalation (breathing in) of the dust.
[22]
Mercury can cause both chronic and acute poisoning.
In the year 1810, over 200 people died of mercury poisoning on the ship
Triumph
because a barrel of mercury had leaked.
Mercury is extremely
poisonous
and has to be used carefully. When mercury is spilled, there are special ways to clean it up.
[23]
Smaller drops should be combined to a larger drop on hard surfaces to be removed more easily (for example, being pushed into a bag that can be thrown away).
Vacuum cleaners
and
brooms
should not be used. This is because they can spread mercury even more. Afterwards, elements such as
sulfur
or
zinc
powder should be sprinkled over the place, then collected and cleaned away. It is not easy to clean mercury entirely off clothing, so it is better not to use them anymore. Breathing in mercury vapor is also very dangerous.
[22]
- ↑
"quicksilver definition"
. Dictionary.com Unabridged (v 1.1)
. Retrieved
October 13,
2008
.
- ↑
"Mercury and the environment ? Basic facts"
.
Environment Canada
, Federal Government of Canada. 2004
. Retrieved
2008-03-27
.
- ↑
"Mercury ? Element of the ancients"
. Center for Environmental Health Sciences,
Dartmouth College
. Retrieved
2008-03-27
.
- ↑
"Qin Shihuang"
. Ministry of Culture,
People's Republic of China
. 2003. Archived from
the original
on 2008-07-04
. Retrieved
2008-03-27
.
- ↑
Wright, David Curtis (2001).
The History of China
. Greenwood Publishing Group. p. 49.
ISBN
031330940X
.
- ↑
Hammond C.R (2000).
The Elements, in Handbook of Chemistry and Physics 81st edition
(PDF)
. CRC press.
ISBN
0849304814
.
- ↑
The radioactive element
francium
may also have a lower melting point, but its radioactivity prevents enough of it from being isolated for direct testing.
"Francium"
. Periodic.lanl.gov. Archived from
the original
on 2010-11-23
. Retrieved
2010-02-23
.
- ↑
Kaner, Richard (2003).
"C&EN: It's elemental: the Periodic Table ? Caesium"
. American Chemical Society
. Retrieved
2010-02-25
.
- ↑
Fred Senese.
"Why is mercury a liquid at STP?"
. General Chemistry Online at Frostburg State University
. Retrieved
May 1,
2007
.
- ↑
Green, J. and Damji, S.
Chemistry
, Melton: IBID Press, 3rd ed. 2007
- ↑
IMA/CNMNC List of Mineral Names
Archived
2013-06-26 at the
Wayback Machine
(PDF 1.8 MB; p 184)
- ↑
L.B. Railsback
Definitions
[1]
Archived
2013-03-02 at the
Wayback Machine
and
[2]
Archived
2012-09-15 at the
Wayback Machine
- ↑
FDA.
"Thimerosal in Vaccines"
.
Food and Drug Administration
. Retrieved
October 25,
2006
.
- ↑
"What happened to Mercurochrome?"
. July 23, 2004
. Retrieved
2009-07-07
.
- ↑
Pimple, K.D. Pedroni, J.A. Berdon, V. (July 9, 2002).
"Syphilis in history"
. Poynter Center for the Study of Ethics and American Institutions at Indiana University-Bloomington. Archived from
the original
on February 16, 2005
. Retrieved
April 17,
2005
.
{{
cite news
}}
: CS1 maint: multiple names: authors list (
link
)
- ↑
Mayell, H. (2007-07-17).
"Did Mercury in "Little Blue Pills" Make Abraham Lincoln Erratic?"
.
National Geographic News
. Retrieved
2008-06-15
.
- ↑
Parker SK, Schwartz B, Todd J, Pickering LK (2004).
"Thimerosal-containing vaccines and autistic spectrum disorder: a critical review of published original data"
.
Pediatrics
.
114
(3): 793?804.
doi
:
10.1542/peds.2004-0434
.
PMID
15342856
.
S2CID
1752023
.
{{
cite journal
}}
: CS1 maint: multiple names: authors list (
link
)
Erratum
(2005).
Pediatrics
115 (1): 200.
doi
:
10.1542/peds.2004-2402
PMID 15630018
.
- ↑
"Thimerosal in vaccines"
. Center for Biologics Evaluation and Research, U.S. Food and Drug Administration. 2007-09-06
. Retrieved
2007-10-01
.
- ↑
"Two States Pass First-time Bans on Mercury Blood Pressure Devices"
. Health Care Without Harm. June 2, 2003. Archived from
the original
on August 13, 2009
. Retrieved
May 1,
2007
.
- ↑
"Title 21?Food and Drugs Chapter I?Food and Drug Administration Department of Health and Human Services Subchapter D?Drugs for Human Use Code of federal regulations"
. United States Food and Drug Administration
. Retrieved
May 1,
2007
.
- ↑
"5. Where do the world's supplies of mercury come from?"
.
www.greenfacts.org
. Retrieved
2018-03-06
.
- ↑
22.0
22.1
"Safety data for mercuric sulphide"
. Oxford University. Archived from
the original
on 2009-09-22
. Retrieved
2009-07-07
.
- ↑
"Mercury: Spills, Disposal and Site Cleanup"
. Environmental Protection Agency
. Retrieved
2007-08-11
.