Dry ice

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Dry ice

Dry ice is solid carbon dioxide

Carbon dioxide

Carbon dioxide is a chemical compound composed of two oxygen atoms covalent bond to a single carbon atom. It is a gas at standard temperature and pressure and exists in Earth's atmosphere in this state....
. It is commonly used as a versatile cooling agent.

Dry ice sublimes, changing directly to a gas

Gas

In physics, a gas is a state of matter, consisting of a collection of particles without a definite shape or volume that are in more or less random motion....
at atmospheric pressure. Its sublimation and deposition point is -78.5 °C (-109.3 °F). Its enthalpy of sublimation (?H_sub) at -78.5 °C (-109.3 °F) is 571 kJ/kg (245 BTU/lb).

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Encyclopedia

Dry ice is solid carbon dioxide

Carbon dioxide

Gas

Coolant

A coolant is a fluid which flows through a device in order to prevent its overheating, transferring the heat produced by the device to other devices that utilize or dissipate it....
, since it is colder than water

Water

Water is a common chemical substance that is essential for the survival of all known forms of life. In typical usage, water refers only to its liquid form or States of matter, but the substance also has a solid state, ice, and a gaseous state, water vapor or steam....
or ice

Ice

Ice is a solid phases of matter, usually crystalline solid, of a non-metallic substance that is liquid or gas at room temperature, such as ammonia ice or methane ice....
and leaves no moisture as it changes state. Dry ice can carbonate

Carbonated water

Carbonated water, also known as sparkling water, fizzy water and seltzer, is plain water into which carbon dioxide gas has been dissolved, and is the major and defining component of most soft drinks....
food that is nearby.

History

In 1835

1835 in science

The year 1835 in science and technology involved some significant events, listed below....
the French

France

France , officially the French Republic , is a country whose Metropolitan France is located in Western Europe and that also comprises various Overseas departments and territories of France....
chemist

Chemist

A chemist is a scientist trained in the science of chemistry. Chemists study the composition of matter and its properties such as density, acidity, size and shape....
Charles Thilorier

Charles Thilorier

Charles Thilorier was a scientist who gave the earliest description of solid carbon dioxide. In 1834 he opened a pressurized container of liquid carbon dioxide, only to find that the cooling produced by the rapid evaporation of the liquid yielded a "snow" of solid CO2, also known as dry ice....
published the first account of dry ice. upon opening the lid of a large cylinder containing liquid carbon dioxide, he noted much of the carbon dioxide rapidly evaporated leaving solid dry ice in the container. Throughout the next 60 years, dry ice was observed and tested by scientists.

Manufacture

Dry ice is readily manufactured:

Gases containing a high concentration of carbon dioxide are produced. Such gases can be a byproduct of some other process, such as producing ammonia
Ammonia

Ammonia is a chemical compound with the chemical formula nitrogenhydrogen. It is normally encountered as a gas with a characteristic pungent odor....
and nitrogen
Nitrogen

Nitrogen is a chemical element that has the symbol N and atomic number 7 and atomic mass 14.00674?. Elemental nitrogen is a colorless, odorless, tasteless and mostly inert diatomic gas at standard conditions, constituting 78% by volume of Earth's atmosphere....
from natural gas
Natural gas

Natural gas is a gas consisting primarily of methane. It is found associated with fossil fuels, in coal beds, as methane clathrates, and is created by methanogenic organisms in marshes, bogs, and landfills....
, or large-scale fermentation
Fermentation

Fermentation may refer to:* Fermentation , the process of energy production in a cell under anaerobic conditions * Ethanol fermentation, a form of anaerobic respiration used primarily by yeasts when oxygen is not present in sufficient quantity for normal cellular respiration...
.
Carbon dioxide-rich gas is pressurized and refrigerated until it changes into its liquid form.
The pressure is reduced. When this occurs some liquid carbon dioxide vaporizes, and this causes a rapid lowering of temperature of the remaining liquid carbon dioxide. The extreme cold makes the liquid solidify into a snow-like consistency.
The snow-like solid carbon dioxide is compressed into either small pellets or larger blocks of dry ice.

Dry ice is typically produced in two standard forms: blocks and cylindrical pellets. A standard block weighing approximately 30 kg is most common. These are commonly used in shipping, because they sublimate slowly due to a relatively small surface area. Pellets are around 1 cm in diameter and can be bagged easily. This form is suited to small scale use, for example at grocery store

Grocery store

A grocery store is a store established primarily for the retailing of food. A grocer, the owner of a grocery store, stocks different kinds of foods from assorted places and cultures, and sells them to customers....
s and laboratories

Laboratory

A laboratory is a facility that provides controlled conditions in which science research, experiments, and measurement may be performed. The title of laboratory is also used for certain other facilities where the processes or equipment used are similar to those in scientific laboratories....
. Dry ice is also not very expensive; it costs around US$

United States dollar

The United States dollar is the unit of currency of the United States and was defined by the Coinage Act of 1792 to be between 371 and 416 grains of silver ....
2 or so per kilogram

Kilogram

The kilogram or kilogrammeThe spelling kilogram is used by the International Committee for Weights and Measures and the U.S....
.

Applications

Dry ice is commonly used to package items that need to remain cold or frozen, such as ice cream, without the use of mechanical cooling

Refrigeration

Refrigeration is the process of removing heat from an enclosed space, or from a substance, and moving it to a place where it is unobjectionable....
. In medicine it was used to freeze warts to make removal easier, although that application is now done with the use of liquid nitrogen

Liquid nitrogen

Liquid nitrogen is a liquefied atmospheric gas produced industrially in large quantities by fractional distillation of liquid air. It is pure nitrogen in a liquid state at very low temperature....
. In the construction industry it is used to loosen floor tiles by shrinking and cracking them, as well as to freeze water in valveless pipes to allow repair. In laboratories, a slurry of dry ice in an organic solvent is a useful freezing mixture for cold chemical reactions.

Dry ice can used to flash freeze food. It is used commercially to flash freeze tuna

Tuna

Tuna are several species of ocean-dwelling fish in the family Scombridae, mostly in the genus Thunnus. Tunas are fast swimmers?they have been clocked at 70 km/h ?and include several species that are warm-blooded....
for sushi

Sushi

In Japanese cuisine, is vinegared rice, usually topped with other ingredients, including fish dishes. In Japan, sliced raw fish alone is called sashimi and is distinct from sushi, as sashimi is the raw fish component, not the rice component....
. It can also be used to flash-freeze laboratory biological samples.

Dry ice can also be used for making ice cream.

It can be used as bait to trap mosquito

Mosquito

Mosquitoes are common flying insects in the family Culicidae that are found around the world. There are about 3,500 species. They have a pair of scaled wings, a pair of halteres, a slender body, and six long legs....
es and other insects

Dry ice can be used in theatre productions in order to create the effect of dense fog. When dry ice is placed in water sublimation

Sublimation

Sublimation can have several meanings:* Sublimation , the change from solid to gas, while at no point becoming a liquid.* Sublimation , the transformation of emotions....
is accelerated, and low-sinking dense clouds of fog (smoke like) are created. This is used in fog machine

Fog machine

A fog machine is a device which emits a dense vapor that appears similar to fog or smoke. This artificial fog or smoke is typicly known as theatrical smoke and fog within the entertainment industry....
s, at theaters, discothèque

Discothèque

A discoth?que, , is an entertainment venue or club with music record played by "Discaires" through a PA system, rather than an Live band dance....
s, Haunted House

Haunted house

A haunted house is defined as a house that is believed to be a center for supernatural occurrences or paranormal phenomena. A haunted house may allegedly contain ghosts, poltergeists, or even malevolent entities such as demons....
s, and nightclub

Nightclub

A nightclub is a Alcoholic beverage, Dance and entertainment Music venue which does its primary business after dark. People who frequent nightclubs are known as clubbers....
s for dramatic effects. Unlike most artificial fog machines, which makes the fog rise up much like smoke, fog from dry ice crawls on the ground.

Dry Ice is also used in cloud seeding

Cloud seeding

Cloud seeding, a form of weather control, is the attempt to change the amount or type of Precipitation that falls from clouds, by dispersing substances into the air that serve as Cloud condensation nuclei or ice nucleus, which alter the microphysical processes within the cloud....
: the process of altering cloud precipitation.

Dry ice blasting

One of the largest alternative uses of dry ice is blast cleaning. Dry ice pellets are shot out of a nozzle with compressed air. This can remove residues from industrial equipment. Examples of materials being removed include ink, glue, oil, paint, mold and rubber. Dry ice blasting can replace sandblasting, steam blasting, water blasting or solvent blasting. The primary environmental residue of dry ice blasting is the sublimed CO₂, thus making it a useful technique where residues from other blasting techniques are undesirable.

Safety

See also: Burn#Causes of burns
Burn

A burn is an injury to the skin caused by heat, cold, electricity, chemicals, or radiation.Burn may also refer to*Concrete things and phenomena:...

Dry ice can cause severe skin damage through cold burns. It is especially dangerous because dry ice produces a lot of fog

Fog

Fog is a cloud bank that is in contact with the ground. A cloud may be considered partly fog; for example, the part of a cloud that is suspended in the air above the ground is not considered fog, whereas the part of the cloud that comes in contact with higher ground is considered fog....
, which can make it hard to see exactly where the dry ice is . Generally, airline passengers are not permitted to bring packages containing dry ice into an airplane cabin.

Dry ice sublimates into large quantities of carbon dioxide gas, which could displace oxygen-containing air and pose a danger of asphyxiation. Thus, it should only be exposed to open air in a well-ventilated environment.

Dry ice

History

Manufacture

Applications

Dry ice blasting

Safety

See also

External links