pt. 2

• bunsen burner Produces a single open gas flame, which is used for heating, sterilization, and combustion.
• triple beam power Used to measure masses very precisely.
• centrifuge Used to separate fluids, gases, or liquids based on the density of the subject.
• autoclave used to decontaminate certain biological waste and sterilize media, instruments, and lab ware.
• hot plate heat source that can uniformly heat solutions and materials.
• test tube rack Used to hold, mix, or heat small quantities of solid or liquid chemicals for laboratory testing or experiments.
• graduated cylinder Used to measure the volume of a liquid. Each marked line on the graduated cylinder represents the amount of liquid that has been measured.
• volumetric flask Used for precise dilutions and preparation of standard solutions.
• erlenmeyer flask Used to contain liquids and for mixing, heating, cooling, incubation, filtration, storage, and other liquid-handling processes.
• beaker It is for stirring, mixing, and heating liquids commonly used in many laboratories.
• numerical aperture Indicates the resolving power of an objective lens. The larger the numerical aperture value, the finer the detail that can be seen.
• depth focus is a Distance between the two planes defines the limits of acceptable image sharpness when the microscope is focused on an object.
• focal length is a distance from the principal point to the focal of a lens.
• parfocal is an Objectives that can be changed with minimal or no refocusing.
• working distance is a Distance between the front end of a microscope objective and the surface of the workpiece at which the sharpest focusing is obtained.
• resolution Determines how finely a lens is able to distinguish the details of a specimen.
• magnification Degree of increase in size of the optical image over the actual size of the object being viewed.
• fluorescence microscope Used to observe the specimen, it begins where a molecule absorbs light of high frequency and emits light of lower frequency.
• phase contract microscope  Useful for looking at specimens that are both colorless and transparent.
• darkfield microscope used to focus incident light, meaning the background stays dark. The light does not pass directly through the sample being studied.
• brightfield microscope Uses light from the lamp source under the microscope stage to illuminate the specimen.
• transmission electron microscope Uses electrons, but instead of scanning the surface (as with SEM's), electrons are passed through very thin specimens.
• scanning electron microscope Allows scientists to view a universe too small to be seen with a light microscope. It does not use light waves; it uses electrons to magnify objects up to two million times.
• light microscope Use compound lenses and light to magnify objects. The lenses bend or refract the light, which makes the object beneath them appear closer.