A funnel is a tube or pipe that is wide at the top and narrow at the bottom, used for guiding liquid or powder into a small opening. Funnels are usually made of

stainless steel Stainless steel, also known as inox, corrosion-resistant steel (CRES), or rustless steel, is an iron-based alloy that contains chromium, making it resistant to rust and corrosion. Stainless steel's resistance to corrosion comes from its chromi ...

aluminium Aluminium (or aluminum in North American English) is a chemical element; it has chemical symbol, symbol Al and atomic number 13. It has a density lower than that of other common metals, about one-third that of steel. Aluminium has ...

glass Glass is an amorphous (non-crystalline solid, non-crystalline) solid. Because it is often transparency and translucency, transparent and chemically inert, glass has found widespread practical, technological, and decorative use in window pane ...

, or

plastic Plastics are a wide range of synthetic polymers, synthetic or Semisynthesis, semisynthetic materials composed primarily of Polymer, polymers. Their defining characteristic, Plasticity (physics), plasticity, allows them to be Injection moulding ...

. The material used in its construction should be sturdy enough to withstand the weight of the substance being transferred, and it should not react with the substance. For this reason, stainless steel or glass are useful in transferring

diesel fuel Diesel fuel, also called diesel oil, heavy oil (historically) or simply diesel, is any liquid fuel specifically designed for use in a diesel engine, a type of internal combustion engine in which fuel ignition takes place without a spark as a re ...

, while plastic funnels are useful in the kitchen. Sometimes disposable

paper Paper is a thin sheet material produced by mechanically or chemically processing cellulose fibres derived from wood, Textile, rags, poaceae, grasses, Feces#Other uses, herbivore dung, or other vegetable sources in water. Once the water is dra ...

funnels are used in cases where it would be difficult to adequately clean the funnel afterwards (for example, in adding

motor oil Motor oil, engine oil, or engine lubricant is any one of various substances used for the lubrication of internal combustion engines. They typically consist of base oils enhanced with various additives, particularly antiwear additives, deterge ...

into a car). Dropper funnels, also called

dropping funnel A dropping funnel or addition funnel is a type of laboratory glassware used to transfer liquids. It is fitted with a stopcock which allows the flow to be controlled. Dropping funnels are useful for adding reagents slowly, i.e. drop-wise. This is d ...

s or tap funnels, have a tap to allow the controlled release of a liquid. A flat funnel, made of

polypropylene Polypropylene (PP), also known as polypropene, is a thermoplastic polymer used in a wide variety of applications. It is produced via chain-growth polymerization from the monomer Propene, propylene. Polypropylene belongs to the group of polyolefin ...

, utilises living hinges and flexible walls to fold flat. The term "funnel" may refer to the chimney or smokestack on a steam

locomotive A locomotive is a rail transport, rail vehicle that provides the motive power for a train. Traditionally, locomotives pulled trains from the front. However, Push–pull train, push–pull operation has become common, and in the pursuit for ...

and commonly refers to the same on a ship. The term ''funnel'' is also applied to other seemingly strange objects like a

smoking pipe A smoking pipe, often simply referred to as a pipe, is used to inhale (or taste) the smoke of a burning substance, typically (though not exclusively) used to consume a Psychoactive drug, psychoactive substance; this most commonly refers to a to ...

or a kitchen bin.

Laboratory funnels

There are many different kinds of funnels that have been adapted for specialised applications in the laboratory, such as

filter funnel A filter funnel is a laboratory funnel used for separating solids from liquids via the laboratory process of filter (chemistry), filtering. In order to achieve this, a cone-like shaped piece of filter paper is usually folded into a cone and placed ...

s and

thistle funnel A thistle tube is a piece of laboratory glassware consisting of a shaft of tube, with a reservoir and funnel-like section at the top. Thistle tubes are typically used by chemists to add liquid to an existing system or apparatus. Thistle funnels a ...

s (shaped like

thistle Thistle is the common name of a group of flowering plants characterized by leaves with sharp spikes on the margins, mostly in the family Asteraceae. Prickles can also occur all over the planton the stem and on the flat parts of the leaves. T ...

flowers).

Dropping funnel A dropping funnel or addition funnel is a type of laboratory glassware used to transfer liquids. It is fitted with a stopcock which allows the flow to be controlled. Dropping funnels are useful for adding reagents slowly, i.e. drop-wise. This is d ...

s have stopcocks which allow the fluids to be added to a flask slowly. For solids, a powder funnel with a wide and short stem is more appropriate as it does not clog easily. When used with

filter paper Filter paper is a semi-permeable paper barrier placed perpendicular to a liquid or air flow. It is used to separate fine solid particles from liquids or gases. The raw materials are typically different pulp (paper), paper pulps. The pulp may be ...

, filter funnels, Büchner and

Hirsch funnel Hirsch is a surname. Notable people with the surname include: * Afua Hirsch (born 1981), Norwegian-born British writer, broadcaster, and former barrister * Alex Hirsch (born 1985), American animator, screenwriter and voice actor * August Hirsch ...

s can be used to remove fine particles from a liquid in a process called

filtration Filtration is a physical separation process that separates solid matter and fluid from a mixture using a ''filter medium'' that has a complex structure through which only the fluid can pass. Solid particles that cannot pass through the filte ...

. For more demanding applications, the filter paper in the latter two may be replaced with a sintered glass frit.

Separatory funnel A separatory funnel, also known as a separation funnel, separating funnel, or colloquially sep funnel, is a piece of laboratory glassware used in liquid-liquid extractions to separate (''partition'') the components of a mixture into two miscible, i ...

s are used in liquid-liquid extractions. The

Tullgren funnel A Berlese funnel or Berlese trap is a device used to extract desiccation-intolerant invertebrates from samples of soil or leaf litter. It works by creating a desiccation gradient over the sample such that mobile organisms will move away from th ...

is used to collect

arthropod Arthropods ( ) are invertebrates in the phylum Arthropoda. They possess an arthropod exoskeleton, exoskeleton with a cuticle made of chitin, often Mineralization (biology), mineralised with calcium carbonate, a body with differentiated (Metam ...

s from

plant litter Plant litter (also leaf litter, tree litter, soil litter, litterfall, or duff) is dead plant material (such as leaves, bark, needles, twigs, and cladodes) that has fallen to the ground. This detritus or dead organic material and its constituent ...

or similar material.

Construction

Glass is the material of choice for laboratory applications due to its inertness compared with metals or plastics. However, plastic funnels made of nonreactive

polyethylene Polyethylene or polythene (abbreviated PE; IUPAC name polyethene or poly(methylene)) is the most commonly produced plastic. It is a polymer, primarily used for packaging (plastic bags, plastic films, geomembranes and containers including bott ...

are used for transferring aqueous solutions. Plastic is most often used for powder funnels that do not come into contact with solvent in normal use.

Uses

* To channel

liquids Liquid is a state of matter with a definite volume but no fixed shape. Liquids adapt to the shape of their container and are nearly incompressible, maintaining their volume even under pressure. The density of a liquid is usually close to th ...

or fine-grained substances into containers with a small opening. Used for pouring liquids or powder through a small opening and for holding the filter paper in filtration. Used in transferring liquids in small containers. * Funnels known as killing cones are used to slaughter individual birds in

poultry farming Poultry farming is the form of animal husbandry which raises domesticated birds such as chickens, ducks, turkeys and geese to produce meat or eggs for food. Poultry – mostly chickens – are farmed in great numbers. More than 60 billion c ...

. The funnel is used to hold a bird upside down so that it can be bled more easily.Sparrey, J., SandercockD., Sparks, N., & Sandilands, V. (2014). Current and novel methods for killing poultry individually on-farm. ''World's Poultry Science Journal,'' ''70''(4), 737-758. doi:10.1017/S0043933914000816

References

External links

* * {{Laboratory equipment Food preparation utensils Laboratory glassware

Laboratory funnels

Construction

Uses

See also

References

External links