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Science Lab Equipment

Identification

Lab

Florence Flask

A Florence flask (also known as a

round bottom flask or a boiling flask)

is a piece of laboratory glassware It

is a round or flat-bottom flask with a long neck It is designed for uniform heating and is produced in a number

of different glass thicknesses to stand different types of use They are often made of borosilicate glass that has alkali to prevent cracks or defacing of the glass The flask is named after

Florence, Italy

Ring, Ring Stand, & Clamp

Erlenmeyer Flask

• An Erlenmeyer flask (also known as a conical

flask) is a type of laboratory glassware which

consists of an inverted conical base with a

cylindrical neck The main advantages in an Erlenmeyer flask are that it is less likely to tip over than a Florence flask and the smaller neck slows evaporative loss better than a beaker It can also be swirled without fear of the contents spilling It is named after the German chemist

Richard Erlenmeyer The conical flask's

counterpart is the beaker However the main difference is that conical flasks may be

stoppered using rubber bungs, so as the

contents of the flask may be mixed or

transported safely The flask is not usually used when heating substances vigorously, this task usually being left to the Florence flask

• A stopper is a truncated conical

piece of rubber or cork used to close off a glass tube, piece of

laboratory glassware, a wine bottle or barrel and other containers with

orifices A rubber stopper is

sometimes called a rubber bung,

and a cork stopper is called cork

Ground glass stoppers are commonly used with laboratory glassware,

mainly because of their nonreactivity.

• A beaker is a type of laboratory glassware which

consists of a cylindrical cup with a notch on the top to allow for the pouring of liquids They are about as wide as they are tall This makes

beakers very stable and easy to handle They may be made of plastic, glass, or Pyrex® Some beakers have graduated markings, or

calibrations, to allow an easy rough measure of liquid volume As a means to make solutions, they are probably the most used piece of

laboratory glassware Coupled with a good

magnetic stirrer, they see frequent heavy use in

a laboratory Like a test tube or a boiling tube, a beaker can be placed over a burning flame (such

as a Bunsen burner) to be heated

Test Tube

• A test tube (Sometimes culture tube) is a kind

of laboratory glassware, composed of a

fingerlike length of glass tubing, open at the top, sometimes with a rounded lip at the top, and a rounded 'U' shaped bottom They range in size from a few centimetres to over 20 centimetres in length and from a few millimetres to several

centimetres in diameter They are designed to allow easy heating of samples, to be held in a flame, and often are made of expansion-

resistant glasses, such as Pyrex Tests tubes are often preferred above beakers when multiple small chemical or biological samples have to be handled and/or stored

Test Tube Rack

Used to store and hold test tubes in an upright position.

Test Tube Holder

Used to hold test tubes, especially when heated or containing harmful chemicals.

Test Tube Brush

Used to clean the insides of test tubes.

Graduated Cylinder

• A graduated (Grad for short) cylinder, also

referred to as a measuring cylinder, is a type of

laboratory glassware that is used for measuring the volumes of liquids in a quantitative manner The top usually has a small curled lip to allow

easy pouring of liquids, and the bottom is usually anchored with a wide base, to keep the cylinder from easily tipping The volumes of liquids

graduated cylinders can handle range from a few

milliliters to many liters A graduated cylinder can

be made of plastic or glass or Pyrex Often, the largest graduated cylinders are made of plastic, making them lighter and more break resistant

Petri Dish

• A Petri dish is a shallow glass or plastic

cylindrical dish that biologists use to culture

microbes It was named after the German

bacteriologist Julius Richard Petri (1852-1921) who invented it in 1877 when working as an assistant to Robert Koch Usually, the dish is partially filled with warm liquid agar along with a particular mix of nutrients, salts and

amino acids and, optionally, antibiotics, that match the metabolic needs of the microbe

being studied (technically referred to as a "

selective medium ") After the agar solidifies, the dish is ready to receive a microbe-laden sample (although to grow some microbes it is often necessary to apply the sample with the hot agar) Modern Petri dishes often have rings

on the lids and bases which allow them to be stacked so that they do not slide off of one

another As well as making agar plates , empty Petri dishes may be used to observe plant

germination, or small animal behaviour.

Culture Dish

Mortar and Pestle

• A mortar and pestle are two tools used with

each other to grind and mix substances The mortar is a bowl-like vessel used to contain a substance Mortars have smooth, rounded

bottoms and wide mouths The pestle is a stick used for pounding and grinding Mortar and

pestles were traditionally used in pharmacies to crush various ingredients prior to preparing an

extemporaneous prescription The mortar and pestle is the most common icon associated with pharmacies For pharmaceutical use, the mortar and the head of the pestle are usually made of porcelain, while the handle of the pestle is made

of wood

• A funnel is a conically shaped pipe, employed

as a device to channel liquid or fine-grained substances into containers with a small

opening The diameter of the spout of a

regular kitchen funnel is about 1 /10 that of the upper bowl The almost cylindrical tube below the conical upper part that opens into the

spout can vary in length Funnels are usually made of either stainless sheet metal or plastic, but sometimes paper funnels are used in

cases where it would be difficult to adequately clean the funnel afterwards (for example, in adding motor oil to a car)

Eye Dropper/Medicine Dropper

Used to mix or dispense small amounts of liquid, a

drop at a time.

Microscope Slide & Cover Slip

• A microscope slide is a thin sheet of glass

used to hold objects for examination under a microscope A standard microscope slide (shown on the right) is 75 x 25 mm (3" X 1") and 1.2 mm thick A range of other sizes is available for various special purposes Since compound or high power microscopes have a very narrow region within which they focus, the object to be viewed ("specimen") is typically placed on the middle of the slide with another, much thinner square (or circle or rectangle) of glass placed over the specimen This smaller

sheet of glass is called a cover slip or cover

glass, and typically measures between 18 and

25 mm on a side The cover glass serves two purposes: (1) it protects the microscope's

objective lens from contacting the specimen, and (2) it creates an even thickness (in wet mounts) for viewing.

Hand Lens/Magnifying Glass

• A magnifying glass is a single convex lens

which is used to produce a magnified image

of an object The lens is usually mounted in

a frame with a handle The magnifying glass is the simplest form of

optical microscope A magnifying glass works by creating a magnified virtual image

of an object behind the lens The distance between the lens and the object must be shorter than the focal length of the lens for

this to occur A lens is a device for either

concentrating or diverging light, usually formed from a piece of shaped glass

studied.

Triple Beam Balance

• A balance (also balance scale, beam balance or

laboratory balance) is used to accurately measure the

mass of an object This class of measuring instrument

uses a comparison technique in its conventional form of a

beam from which a weighing pan (weighing bason) and

scale pan (scale bason) are suspended To weigh an

object, it is placed on the measuring pan, and standard

weights are added to the scale pan until the beam is in

equilibrium

• Tongs are gripping and lifting tools , of which there are many forms adapted to their specific use

Safety Goggles

• Goggles or safety glasses are

a form of protective eyewear that usually enclose the eye area to prevent particulates or chemicals from striking the eyes They are used in chemistry laboratories

and in woodworking

Hot Plate

• A hot plate is a small electric stove

often used in a laboratory setting to heat glassware Some hotplates

also contain a magnetic stirrer ,

allowing the heated liquid to be

stirred simultaneously Hot plates are also used in food preparation, generally for small dishes in places where a full kitchen stove would

not be convenient.

• A scalpel is a very sharp knife used for

surgery as well as various arts and crafts Scalpels can have a fixed blade, or a

disposable blade The blades on scalpels are extremely sharp—merely touching a

medical scalpel with bare hands to test it will cut through the skin The handles of

medical and dissection scalpels are flatter, more like a bread knife They do not have the same level of grip as art scalpels, as this would make cleaning and sterilization more difficult The grip in medical scalpels is

usually just a slight corrugation.

• Forceps are a hand-held instrument for grasping

and holding objects, similar in concept to tongs,

mechanism to ensure they do not squeeze too tightly onto the object they are used upon.

Dissecting Pins

Used to hold objects in place during dissection.

• Probe is a generic term used to refer to a

device used to gather information.

Other Equipment

Bunsen Burner

• A Bunsen burner is a device used in scientific

laboratories for heating, sterilization, and many

other uses There is a misconception that the

inventor is Robert Wilhelm Bunsen but it is only

named after him, whose laboratory assistant,

Peter Desdega , in 1855 perfected an earlier design

by Michael Faraday The device safely burns a

continuous stream of gas without the risk that the flame will travel back down the tube to the gas

supply It is most common for the burner today to run on natural gas The burner has a weighted

base, where the gas supply attaches, and a vertical tube rising from it The gas flows from the gas

supply connection to the base The stream of gas then passes through a small hole at the bottom of the tube and is directed upward through the tube There are perforations in the side of the tube at the bottom to admit air into the stream (via the venturi effect and the gas burns at the top of the tube, once

it is ignited The in-flow of gas and thus the heat of the flame can be controlled by adjusting the size of the holes at the base of the tube.

Inoculation Loop

• An inoculation loop (sometimes called smear loop) is a

simple tool used mainly by microbiologists to retrieve an inoculum from a culture of microorganisms Its tip is a wire made of platinum or nichrome, which is not as good but less expensive The wire forms a small loop with a diameter of about 5 mm This loop is handy for taking an inoculum from a liquid by using the phenomenon of

surface tension The inoculation loop is always sterilized

in a flame until it becomes red hot before and after each use By doing this, the same tool can be reused in

different experiments without fear of

cross-contamination